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Invoice Payment Terms: Net 10, Net 30 and More

A person writing dates into a desk calendar planner
In this guide
  1. What are invoice payment terms?
  2. The most common payment terms
  3. What does Net 10 mean?
  4. How Net 30 works in practice
  5. Early-payment discounts: what 2/10 net 30 means
  6. How to choose the right terms
  7. What shorter and longer terms cost you
  8. How payment terms differ by industry
  9. How to write payment terms on an invoice
  10. Payment terms for deposits, milestones and retainers
  11. Where the clock starts
  12. Three real-world examples
  13. Late payment: what the terms should say, and what the law may add
  14. Negotiating payment terms
  15. Terms for international clients
  16. Mistakes to avoid
  17. What to do when the due date passes
  18. Payment terms, payment methods and payment schedules
  19. How to count the days: worked examples
  20. Payment terms in contracts and standard terms and conditions
  21. How payment terms show up in your accounts
  22. Common objections and how to answer them
  23. A simple payment terms policy you can adopt
  24. Checking a client before you give credit
  25. Matching your terms to your own bills
  26. Planning cash with your terms
  27. How the payment method changes how fast you are paid
  28. Terms for different kinds of documents
  29. Quick answers about payment terms
  30. A checklist for payment terms
  31. Put it into practice

Payment terms are the part of an invoice that decides when you get paid. They tell your client how many days they have, whether there is a reward for paying early and what happens if they pay late. Two invoices for the same amount can land in your bank account a month apart purely because of the terms printed on them.

This guide explains what the common terms mean, shows how to count the days, walks through early-payment discounts with the maths, and helps you choose and write terms that suit you. When you are ready to put them on an invoice, the free invoice generator has a payment terms menu that fills in the due date for you.

Quick answer: “Net 30” means the full amount is due 30 days after the invoice date. “Due on receipt” means pay immediately. “2/10 Net 30” means a 2% discount if paid within 10 days, otherwise the full amount in 30 days. Always show the term and the actual due date.

What are invoice payment terms?

Payment terms are the conditions under which you expect to be paid. At a minimum they answer one question: by when? Good terms also say how the client can pay, what happens if they pay late and whether there is a reward for paying early.

Terms appear on the invoice, but they should be agreed earlier: in the quote, the contract or the email that starts the work. The invoice then repeats them. A client who first sees terms on the invoice may reasonably say they never agreed. For the wider process, see how to make an invoice.

The most common payment terms

TermWhat it meansTypical use
Due on receiptPay as soon as the invoice is receivedSmall jobs, consumers, new clients
Net 7Due 7 days after the invoice dateFast-moving freelance work
Net 10 / Net 14Due within 10 or 14 daysSmall businesses and short projects
Net 15Due within 15 daysFreelancers and agencies
Net 30Due within 30 daysThe standard for business-to-business
Net 45 / Net 60Due within 45 or 60 daysLarge companies, public bodies
Net 90Due within 90 daysSome industries; hard on cash flow
EOMDue at the end of the month in which the invoice was issuedSome wholesale and trade accounts
Net 30 EOMDue 30 days after the end of the invoice monthGives clients longer than plain Net 30
CODCash on deliveryPhysical goods
CIACash in advance, before work or shippingHigh-risk or custom orders
50% upfront, 50% on completionSplit paymentProjects and larger jobs

“Net” means the full amount, without deducting a discount. “Net 30” and “30 days” are used interchangeably in practice.

What does Net 10 mean?

Net 10 means the full invoice amount is due within 10 days of the invoice date. “Net” means the total after any discounts, and the number is the days allowed to pay. So an invoice dated 1 November on Net 10 terms is due on 11 November.

TermDue date for an invoice dated 1 NovemberTypical use
Net 78 NovemberSmall jobs, individuals, new clients
Net 1011 NovemberSmall businesses and services that want fast cash
Net 1516 NovemberA common middle ground
Net 301 DecemberStandard business-to-business
Net 4516 DecemberLarger organisations
Net 6031 DecemberLarge companies, public bodies

Net 10 is a good fit when your costs arrive quickly, for example materials or subcontractors, and when you work with small businesses who can pay without an approval chain. It is less realistic with large companies, which often have fixed payment runs and may need 30 days or more.

To use it, write it as a date as well as a term: “Net 10, due 11 November 2026”. For how to write terms on an invoice and how to choose between them, read on.

How Net 30 works in practice

Take an invoice dated 1 October with Net 30 terms. Thirty days after 1 October is 31 October, so the due date is 31 October. The client has until the end of that day.

A few details trip people up:

  • Calendar days, not business days. Net 30 counts every day, including weekends and holidays, unless the contract says otherwise.
  • Weekends and holidays. If the due date falls on a weekend, many clients pay on the next working day, and some pay on the previous one. Say what you expect if it matters.
  • The clock starts on the invoice date. If you date the invoice 1 October but email it on 8 October, the client effectively has 23 days. Send invoices on the day they are dated.
  • Receipt of the invoice. Some large buyers measure from the day they receive or approve the invoice, not from the date on it. If their terms say so, the date they received it is what counts.

In the invoice generator, pick “Net 30” and the due date appears automatically, so you do not have to count.

Early-payment discounts: what 2/10 net 30 means

Some suppliers offer a discount for fast payment. The classic notation is 2/10 net 30:

  • 2 is the discount percentage.
  • 10 is the number of days within which the discount applies.
  • Net 30 is the date by which the full amount is due.

So the buyer can deduct 2% if they pay within 10 days, and must pay in full within 30 days otherwise.

Example. An invoice for $5,000 on 2/10 net 30:

Payment dateAmount to pay
Within 10 days$4,900 (2% off)
Day 11 to day 30$5,000
After day 30$5,000 plus any late fee

Is the discount worth offering?

A 2% discount for paying 20 days earlier looks small, but over a year it is a very high rate of return, which is why many businesses take such discounts:

Annualised cost = discount ÷ (1 − discount) × 365 ÷ (days saved) = 0.02 ÷ 0.98 × 365 ÷ 20 ≈ 37% a year

That is the effective annual cost to you of giving the discount. If you are short of cash, it may still be cheaper than borrowing; if you are not, it is an expensive way to be paid sooner. Offer it only when the faster money is worth that much to you. If you do, state it plainly on the invoice and keep the full due date visible too.

How to choose the right terms

There is no single right answer. These factors should drive your choice.

FactorPushes you toward shorter termsAllows longer terms
Size of the jobSmall or one-off jobsLarge, ongoing contracts
Your cash positionYou have bills to pay nowYou have a healthy buffer
Client typeNew, individual or unknown clientsEstablished companies with a track record
Industry normFreelance and creative workWholesale, construction, public sector
Risk of non-paymentHigher risk or little informationLow risk, credit-checked buyers
CompetitionYou are the only optionCompetitors offer longer terms

Some practical rules of thumb:

  • New clients: shorter terms, a deposit or payment in advance.
  • Repeat clients with a good record: Net 14 or Net 30 is fair.
  • Large companies: expect to be asked for Net 45 or Net 60. You can accept, or ask for a shorter period or a higher price to cover the cost.
  • Big projects: split into stages with an invoice for each. See deposit and progress invoices.

A clock on a desk among scattered pencils and papers

What shorter and longer terms cost you

Terms are not just a date; they are a loan you make to your client. The longer the term, the more of your money sits in their account.

Suppose you invoice about $20,000 a month. With Net 15, roughly half a month’s sales, about $10,000, is outstanding at any time. With Net 30, about a month’s sales, $20,000, is outstanding. With Net 60, it is about $40,000. That extra $20,000 to $30,000 has to be financed from your own pocket, your overdraft or a lender.

This is why, for a small business, shortening terms by 15 days can matter as much as winning a new client. It is also why late payment is such a common cause of cash-flow trouble even in profitable businesses. See how to get paid faster for practical ways to speed it up.

How payment terms differ by industry

Norms vary a lot, and knowing yours helps you set terms that look reasonable to a client.

IndustryCommon termsWhy
Freelance and creativeDue on receipt to Net 14, deposits on larger jobsSmall amounts, one-person cash flow
Consulting and agenciesNet 15 to Net 30Retainers and monthly billing
Construction and tradesStage payments, Net 14 to Net 30, retention in some contractsLong jobs with materials
Wholesale and distributionNet 30, EOM, 2/10 net 30Trade credit is part of the business model
ManufacturingNet 30 to Net 60Long supply chains
Software and subscriptionsDue on renewal date, annual in advanceRecurring, automated billing
Government and public sectorNet 30 to Net 60, sometimes set by policySet by procurement rules
Retail and e-commercePayment at orderConsumers pay immediately

When in doubt, ask a competitor or a colleague what terms they use, or look at what your largest clients already expect.

How to write payment terms on an invoice

Clear terms are short, specific and visible. Put them near the total, in plain words, and repeat the due date.

SituationExample wording
StandardPayment due within 30 days of the invoice date. Due date: 31 October 2026.
ShortDue on receipt.
With discount2% discount if paid within 10 days (by 11 October). Net 30.
Deposit50% deposit due on acceptance; balance due within 14 days of completion.
Stage paymentStage 2 of 3, due 14 days from the invoice date.
With payment methodPlease pay by bank transfer to the account below, quoting the invoice number.
With late feeOverdue balances are charged interest at 1.5% per month.

A few drafting tips:

  • Name the date. “Net 30” is clear to accountants, but some people do not know the shorthand. Add “Due 31 October 2026”.
  • Use the same words as the contract. If the quote says “14 days from the invoice date”, the invoice should too.
  • Avoid vague terms such as “prompt payment” or “as soon as possible”.
  • Say how to pay. Terms and payment instructions belong together.
  • Do not hide terms in small print. Put them where the total is.

Payment terms for deposits, milestones and retainers

Different billing patterns use terms in different ways.

Deposits. The deposit invoice is usually due on receipt or within 7 days, because the work does not start until it is paid. The final invoice then shows the deposit as already paid.

Milestones. Each milestone invoice has its own term, often Net 14, tied to a deliverable. Say what the milestone is: “Milestone 2: design approved”.

Retainers. A monthly retainer is usually invoiced in advance, due on receipt or on the first of the month. Say the period covered.

Subscriptions. Terms are due on the renewal date, normally by card or direct debit, so there is no gap.

Time and materials. Invoice weekly or fortnightly with Net 14 to keep the balance small.

Where the clock starts

The same term can mean different dates depending on the starting point. State it.

Starting pointExampleNote
Invoice dateNet 30 from 1 October is 31 OctoberThe usual default
Date receivedNet 30 from the day the client received itCommon in large companies’ policies
Delivery or completionNet 30 after deliveryUseful for goods and projects
End of month (EOM)Net 30 EOM on an October invoice is 30 NovemberGives clients longer
Approval dateNet 30 after sign-offUsed on some projects and by public bodies

If you and the client disagree about the start date, you will disagree about the due date. A single sentence in the contract removes the problem.

Three real-world examples

A freelance designer, small job. Invoice for $600, new client. Terms: due on receipt, with bank transfer details. The designer sends the invoice the day the files are delivered and a polite reminder the following Monday. Paid in 5 days.

A small agency, monthly retainer. Invoice for $3,500 on the first of each month, Net 15. The agency states the period covered and the due date. The client’s accounts team schedules payment automatically on the 15th.

A builder, stage payments. A $24,000 extension split into a 30% deposit, 40% at first fix and 30% on completion. Each invoice is Net 7, because the builder needs the cash to pay suppliers. The final invoice states the earlier payments and the balance.

In each case the terms were agreed up front and repeated on the invoice, and the invoice was sent on the date it was due to start the clock.

Late payment: what the terms should say, and what the law may add

Terms are only useful if there is a consequence for ignoring them. Two things matter: what you and your client agreed, and what the law adds.

What you agreed. A late fee or interest rate agreed in advance, written on the invoice, is the clearest basis. Our guide to invoice late fees shows wording and typical rates.

What the law may add. Some countries set default rules for business-to-business payments. In the United Kingdom, the Late Payment of Commercial Debts (Interest) Act lets a business charge statutory interest of 8% above the Bank of England base rate on late business-to-business payments, unless the contract sets a different rate, and a fixed sum for recovery costs. In the European Union, the Late Payment Directive sets a general limit of 60 days for business-to-business payments unless expressly agreed otherwise and not grossly unfair, interest of at least 8 percentage points above the reference rate, and a minimum fixed recovery sum of 40 euros. Each member state applies this in its own law. In the United States there is no equivalent federal rule; late fees depend on the contract and on state law.

These are general descriptions, not legal advice. Rules change and have exceptions, so check current official guidance for your country before relying on them.

Negotiating payment terms

When a larger client proposes longer terms than you want, you have options.

  1. Ask for shorter. “Our standard terms are Net 14. Could you do that?” Many clients agree if asked.
  2. Trade terms for price or deposit. Accept Net 45 with a 30% deposit, or a slightly higher price to cover the cost of waiting.
  3. Offer an early-payment discount. 2/10 net 45 gives them a reason to pay sooner.
  4. Split the work. Smaller invoices at earlier milestones reduce what is outstanding at any time.
  5. Get it in writing. Whatever you agree, confirm in the contract or an email.

If a client insists on terms you cannot afford, you can also decline, or ask whether they have a faster route for small suppliers; some companies and public bodies have one.

Terms for international clients

When your client is in another country, terms need a few extra words.

  • State the currency next to the total and in the terms.
  • Say who pays bank charges. “Amount received in full, with transfer fees paid by the sender.”
  • Allow for transfer time. A cross-border payment can take several days, so give a due date, not just “payment on receipt”.
  • Check local rules. Some countries limit payment terms or require interest, and some tax authorities expect invoice terms in a particular form.
  • Consider payment in advance for first-time overseas clients.

See invoicing international clients for more.

Mistakes to avoid

MistakeWhy it hurtsFix
No terms on the invoiceThe client sets their ownAlways state terms and a due date
Terms differ from the quoteThe client disputes the invoiceCopy terms from the quote
Only a shorthand like “N30”Some clients do not know itWrite “Net 30, due 31 October”
Due date falls before the invoice arrivesThe invoice is late on day oneSend on the invoice date
Long terms by defaultStarves cash flowChoose terms deliberately
Late fee not agreed in advanceDisputes and refusalsAgree it in the contract
No follow-up on the due dateOverdue invoices driftChase the next day

What to do when the due date passes

Terms are only useful if you act on them. A simple routine:

  1. Day before the due date: an optional friendly reminder with the invoice attached.
  2. The day after: a short, polite message asking when payment will be made.
  3. A week after: a firmer reminder quoting the terms and any late fee.
  4. Two to three weeks after: a phone call and a final written notice.
  5. After that: follow the escalation path you agreed, whether a collections step or legal advice.

The invoice reminder email templates give ready-to-send wording for each stage, and how to get paid faster has more tactics.

Payment terms, payment methods and payment schedules

These three phrases are often mixed up, and keeping them apart makes invoices clearer.

ConceptQuestion it answersExample
Payment termsWhen is the money due?Net 30, due on receipt
Payment methodsHow can it be paid?Bank transfer, card, payment link
Payment scheduleIn what instalments?30% on acceptance, 40% at first fix, 30% on completion

An invoice should contain all three where they apply. A single line of terms (“Net 30”) with no method leaves the client to guess how to pay, and a schedule with no due dates leaves them to guess when.

How to count the days: worked examples

Counting is easy to get wrong when a term crosses a month boundary. These examples use calendar days.

Invoice dateTermDue date
1 October 2026Net 1415 October 2026
15 October 2026Net 3014 November 2026
1 October 2026Net 4515 November 2026
1 October 2026Net 6030 November 2026
10 October 2026Net 30 EOM30 November 2026
31 January 2026Net 302 March 2026

The last row shows the trap: 30 days after 31 January is not the end of February, because February is short. A generator that calculates the due date from the invoice date, as the invoice generator does when you choose a term, avoids counting by hand.

Payment terms in contracts and standard terms and conditions

Larger clients often have their own standard terms, and your invoice terms interact with them.

  • Your terms and theirs. If your quote says Net 14 and their purchase order says Net 45, you have a conflict. Resolve it before work starts, not at invoicing.
  • “Battle of the forms”. When each side has standard terms, the terms that apply may depend on what was last accepted. Do not rely on small print; agree the payment terms expressly.
  • Master agreements. If you work under a framework agreement, its payment clause usually governs every invoice. Quote the agreement number on the invoice.
  • Quotes and acceptance. A signed quote or an email that says “yes, go ahead” with your terms attached is usually enough evidence of agreement.

A short clause is all you need in your own terms: “Invoices are payable within 14 days of the invoice date. Late payments incur interest at 1.5% per month.”

How payment terms show up in your accounts

Payment terms drive an important accounting view: the ageing of your receivables, which shows how old each unpaid invoice is.

BucketMeaningTypical action
CurrentNot yet dueNone
1 to 30 days past dueSlightly lateFriendly reminder
31 to 60 days past dueLateFirm reminder, phone call
61 to 90 days past dueSeriously lateWritten notice, consider stopping work
Over 90 daysAt riskEscalate; consider whether to write off

Reviewing this list every week or two takes minutes and tells you which clients need a nudge. It also shows whether your terms are working: if most invoices fall in “1 to 30 days past due”, your terms may be too long or your reminders too late.

Common objections and how to answer them

What the client saysA reasonable answer
“Our policy is to pay in 60 days.”“We can do 60 days with a 30% deposit, or 30 days at the quoted price.”
“We pay on the 25th of the month after the invoice.”“That works if the invoice arrives by the 20th. Let me confirm the cutoff.”
“We never agreed to those terms.”“They were in the quote you accepted on the 12th. I have attached it for reference.”
“Can we pay in instalments?”“Yes, we can split it into two payments, 50% now and 50% in 14 days.”
“Can we get a discount for paying early?”“We offer 2% if paid within 10 days.”
“Our finance team has not received it.”“I will resend it now. Please confirm the right address.”

Having these answers ready keeps conversations short and friendly, and it keeps you from making concessions you will regret.

A simple payment terms policy you can adopt

Write your policy in one short paragraph and keep it with your quote template:

Payment policy. Projects under $1,000 are invoiced on completion, due within 7 days. Larger projects are invoiced in stages: 30% on acceptance, 40% at the midpoint and 30% on completion, each due within 14 days. Recurring work is invoiced monthly in advance, due on the first of the month. Overdue balances accrue interest at 1.5% per month and work may be paused until the balance is cleared.

A policy like this does three things. It saves you deciding each time, it makes you look professional and it gives you something to point to if a client resists. Adjust the numbers to your business and keep it consistent.

Checking a client before you give credit

Every set of terms other than payment in advance is a form of credit, so it is reasonable to look at who you are lending to. A few quick checks take minutes:

  • Is the client a registered company? Look up the registration in your country’s company register and check that the name and address match the contract.
  • How long have they existed? A business that has traded for years is a lower risk than one set up last month.
  • Do they pay others on time? Ask for a trade reference, or ask other suppliers in your network. Public filings in some countries show payment behaviour.
  • Is the order unusually large for them? A first order far bigger than their usual size is a reason to ask for a deposit.
  • Do the details match? An address that is a mailbox or an email from a free address on a large order is worth a second look.

If anything looks uncertain, shorten the terms, ask for a deposit or invoice in stages. You can always extend credit later once a client has paid on time a few times.

Matching your terms to your own bills

Your payment terms should also reflect the terms your own suppliers give you. If you have to pay a supplier in 14 days but your client pays in 45, you are financing 31 days out of your own pocket.

Your supplierYour clientGap you must finance
Net 30Net 14You are paid before you pay
Net 14Net 3016 days
Net 14Net 6046 days
Pay nowNet 4545 days

Where there is a gap, you can close it by shortening your terms, asking for a deposit, negotiating longer terms with your supplier or setting aside a cash buffer. Looking at the two sets of terms together is one of the quickest ways to find out whether your business model works.

Planning cash with your terms

Payment terms let you forecast when money arrives. A simple four-week view for a business invoicing $4,000 each week on Net 14 would look like this:

WeekInvoicedCash receivedOutstanding at end
1$4,000$0$4,000
2$4,000$0$8,000
3$4,000$4,000 (week 1)$8,000
4$4,000$4,000 (week 2)$8,000

The business is invoicing $4,000 a week but only starts receiving it in week 3, and has $8,000 owed to it at any time. If those terms became Net 30, the outstanding balance would roughly double. A forecast like this helps you decide whether you can afford a larger client on long terms, or whether you need a deposit.

How the payment method changes how fast you are paid

The same due date can result in money arriving on different days, depending on how it is paid.

MethodTypical time to receive the moneyNotes
Card or online walletSame day to a couple of daysFees apply; fast
Bank transfer, same countrySame day to 2 daysCheap; depends on banking hours
Bank transfer, international1 to 5 daysFees and currency conversion
Direct debitA few days after collectionNeeds a mandate
ChequeA week or morePosting and clearing time
CashImmediateNeeds a receipt

If you want to be paid by the due date, make the fastest sensible method the easiest. A payment link or complete bank details on the invoice removes a common delay.

Terms for different kinds of documents

Payment terms apply mainly to invoices, but other documents interact with them:

  • Quotes and estimates should state the terms you will use, so the invoice contains no surprise. See quote vs estimate vs invoice.
  • Proforma invoices are used for advance payment, so the terms are “payment before shipment”. See pro forma vs commercial invoice.
  • Credit notes do not have payment terms; they reduce the amount due on an earlier invoice. See what a credit note is.
  • Recurring invoices repeat the same terms each period; state the period.
  • Purchase orders can carry the buyer’s terms, so check them before you accept. See purchase order vs invoice.

Quick answers about payment terms

Is “Net 30” the same as “30 days”? In practice, yes. “Net 30” is the formal shorthand.

Can I use “due in 14 days” instead of “Net 14”? Yes. Plain words are often clearer, and you can add the date.

What if I forget to put terms on the invoice? The client may apply their own policy, or the default in the contract or in local law. Send a short note confirming the terms you agreed and use them from the next invoice.

Should terms be the same for all clients? A standard default is useful, but you can vary it by client size and risk. Document the exceptions.

Do payment terms affect tax? Not usually the amount of tax, but the invoice date and the supply date matter for when tax is reported. Ask your accountant if you account on an invoice basis or a cash basis.

What is the difference between payment terms and a payment plan? Terms say when a single invoice is due. A payment plan splits one debt into instalments, usually agreed because the client cannot pay in one go. Put the plan in writing with dates and amounts.

Can a client pay earlier than the due date? Always. The due date is the last day, not the first, and paying early is welcome.

A checklist for payment terms

CheckDone
Terms agreed in the quote or contract
The invoice states the term and the due date
The clock’s starting point is clear
Payment methods and details are on the invoice
Any early-payment discount is stated, with its deadline
Any late fee was agreed beforehand and is shown
The currency is clear for international clients
A reminder is scheduled for the day after the due date

Put it into practice

Start with the terms you are comfortable with, because they are the ones you will enforce. Write them down once, put them in every quote, and let the invoice repeat them. Review them once a year: if more than a handful of invoices a month are paid late, the terms are probably too long, the reminders too late or the invoices too unclear, and each of those has a simple fix.

Choose the terms that match your cash flow and your client, confirm them in writing, and show both the term and the date on every invoice. The invoice generator has a payment terms list (due on receipt, Net 7 to Net 90 or a custom date) and calculates the due date, and the guide on what to include on an invoice shows where terms sit among the other elements.

Frequently asked questions

What does Net 30 mean on an invoice?

Net 30 means the full invoice amount is due 30 days after the invoice date. An invoice dated 1 October with Net 30 terms is due on 31 October. The word 'net' refers to the full amount, with no discount.

What are the most common invoice payment terms?

Due on receipt, Net 7, Net 14, Net 15, Net 30, Net 45 and Net 60 are the most common. Net 30 is the usual standard for business-to-business work, while freelancers and small jobs often use Net 14 or due on receipt.

What does 2/10 net 30 mean?

It means the buyer may take a 2 percent discount if they pay within 10 days, otherwise the full amount is due in 30 days. It rewards early payment and is mainly used by suppliers who want faster cash.

What is the difference between due on receipt and Net 0?

They both mean payment is expected immediately. Due on receipt is the more common way to write it. In practice many clients still take a few days to process it, so state a due date as well.

Do payment terms start from the invoice date or the delivery date?

Normally from the invoice date, but the contract can say otherwise, for example 30 days from delivery or from the end of the month. State clearly which date the clock starts from.

How do I choose the right payment terms?

Consider the size of the job, your cash flow, the client's size and habits, and industry norms. Shorter terms and deposits suit small or new clients; longer terms may be a trade-off for large clients. Whatever you pick, agree it in the quote or contract before the invoice.

Can I change payment terms after sending an invoice?

Only by agreement. Changing terms unilaterally after the invoice is sent is likely to be refused and can damage the relationship. If terms need to change, agree it in writing and issue a corrected invoice.

Are payment terms legally binding?

Payment terms that are agreed in a contract, quote or accepted invoice are generally binding on both parties. Some countries also set maximum payment periods or default interest rules for business-to-business payments, so check the law where you operate.