Invoice Due Date Calculator

DateMath adds the net days to the invoice date as calendar days, weekends and holidays included, so Net 30 on an invoice of the 3rd is due 30 days later. For EOM terms DateMath counts from the last day of the invoice's month instead: EOM alone is due on that day, and Net 30 EOM 30 days after it. An early-payment discount counts from the same day as the net days, so 2/10 Net 30 gives the discount until day 10. A due date on a weekend or federal holiday stays where the terms put it, and DateMath names the next business day.

• Invoice payment terms. DateMath reads payment terms the way invoices commonly write them: Net 30 is due 30 days after the invoice date, EOM terms count from the end of the invoice's month (Net 30 EOM is due 30 days after it), due on receipt is due on the invoice date, and 2/10 Net 30 gives a 2% discount if paid within 10 days, with the full amount due in 30. Source: Invoice payment terms (SuperfastCPA), Net 30 and Net 30 EOM (Flexprice).
• US federal holidays. DateMath skips the 11 annual holidays of 5 U.S.C. 6103 on the days they are observed for federal employees, as the US Office of Personnel Management (OPM) lists them: a Saturday holiday on the Friday before, a Sunday holiday on the Monday after. Source: 5 U.S.C. 6103, OPM federal holidays.

DateMath's date math is tested against more than 100 cases worked out by hand. Every worked example and table on the site is computed with the same code the calculators run, so a page and its calculator can't disagree.

A due date is the invoice date plus the days in the payment terms. DateMath counts them as calendar days, weekends and holidays included, the way Net terms are written: Net 30 on an invoice dated Wednesday, March 3, 2027 is due Friday, April 2, 2027. EOM terms start the count at the end of the invoice's month instead, and due on receipt needs no count at all.

For any other number of days, type it in the Net days field. Months are not a fixed number of days, so Net 30 is the same day number a month later only after a 30-day month; for terms written in months, such as “payment within 2 months”, add months with the date calculator.

Net 30 counts from the invoice date, so every invoice gets the same 30 days. Net 30 EOM counts from the last day of the invoice's month, so every invoice of one month is due on the same day, and the buyer gets between 30 and 60 days. Sellers and buyers use EOM terms to pay a whole month's invoices in one run.

“EOM” on its own usually means due on the last day of the invoice's month, and the calculator reads it that way. Some businesses write EOM as short for Net 30 EOM, and a few count from the end of the month the invoice was received in. If the terms are unclear, ask, or pick the reading in the calculator that the contract states.

Terms such as 2/10 Net 30 offer a discount for paying early: 2% off if paid within 10 days, otherwise the full amount within 30. The discount days count from the same day as the net days, the invoice date for Net terms and the month end for EOM terms. Tick “Early-payment discount” and the calculator gives the last day to take it; enter the amount and it gives the payment too: on 2,500.00, 2/10 Net 30 means paying 2,450.00 by day 10 instead of 2,500.00 by day 30.

Paying early is a short loan to the seller, so the discount works like interest: keeping 2% for paying 20 days early is 2/98 for 20 days, about 37.2% a year as simple interest. That is why buyers with cash on hand usually take it.

Net days are calendar days, so a due date can land on a Saturday, a Sunday or a holiday. The terms don't move it; the calculator keeps the date and names the next business day. Net 30 on an invoice dated Thursday, January 28, 2027 is due Saturday, February 27, 2027, a Saturday; the next business day is Monday, March 1, 2027.

Whether a payment on that next business day is still on time depends on the contract and on how the payee treats it. Bank transfers don't settle on weekends, so to be safe, send the payment so it arrives on the business day before.

The “Status today” line counts from today's date on your device: “Due in 12 days”, “Due today”, or “Overdue by 5 days” from the day after the due date. Use it to sort open invoices, or to see how late a payment is before you send a reminder. For the business days left until a due date, enter today and the due date in the business days calculator.

With the invoice date in A2:

• Net 30: =A2+30, formatted as a date.
• EOM: =EOMONTH(A2, 0) gives the last day of the invoice's month.
• Net 30 EOM: =EOMONTH(A2, 0)+30.
• 2/10 discount date: =A2+10.
• Next business day when the due date is on a weekend or holiday: =WORKDAY(A2+30-1, 1, holidays), with the observed holidays in the holidays range.
• Days overdue: =MAX(0, TODAY()-(A2+30)).

• Write the due date, not only the terms. “Net 30, due April 2, 2027” leaves nothing to work out, and the client's accounts payable team doesn't have to read the terms the same way you do.
• Shorter terms get paid sooner. Freelancers and small businesses often use Net 7, Net 15 or due on receipt; larger clients often ask for Net 30, Net 60 or EOM terms to fit their payment runs.
• A discount costs you its yearly rate. 2/10 Net 30 gets cash 20 days sooner for 2% of the invoice; offer it only when getting paid sooner is worth that much to you.
• Count from the invoice date you send. Date the invoice on the day you send it, so the client has the full term from receiving it.

For a deadline counted in business days, such as “payment within 10 business days”, use the business days calculator; for a court deadline, the court date calculator.