{{ summaryHeading }} {{ summaryValue }} {{ summaryLine }} {{ statusBadge }}{{ ' ' }} {{ weekendBadge }}{{ ' ' }} {{ adjustmentBadge }}
Enter the explicit date that starts the selected payment term.
The term produces a base date before any final weekend or holiday move.
Use a whole number from 0 to 3,650.
days
Choose day 1 through 31; short months are capped at month end.
Use 31 unless the governing terms explicitly roll late-month invoices forward.
day
Match the payer, bank, office, or contract calendar you intend to use.
This switch changes business-day terms only.
{{ params.count_invoice_date_business ? 'Count a payable anchor as day one' : 'Start after the anchor date' }}
Choose the explicit rollover rule from the governing terms.
Accepted leading dates: 2026-05-25, 2026/5/25, or 5/25/2026.
Use today, a reminder date, or another explicit checkpoint.
{{ workflowFeedback }}
Choose the on-screen presentation; ISO dates remain canonical.
StageDateDays from invoiceMeaningCopy
{{ row.stage }}{{ formatDate(row.date) }}{{ signedDays(row.offset) }}{{ row.meaning }}

Term result

{{ termGuidance }}

Calendar check

{{ calendarGuidance }}

Use boundary

{{ statusGuidance }} Confirm the governing anchor event, payment wording, and closure calendar before reminders, penalties, collections, or payment authorization.

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An invoice date and a payment due date are often separated by more than a simple count of days. The governing document may start the clock at issue, receipt, delivery, acceptance, or approval. Choosing the wrong anchor can move every later reminder, approval, and collection action even when the arithmetic is flawless.

Payment wording also decides what gets counted. Net terms normally add calendar days, while a business-day term skips the recurring non-working weekdays and closure dates that apply to the payer or agreement. End-of-month terms use a month boundary, and some contracts move late-month invoices to the following month end before adding extra days.

Term patternBase-date ideaQuestion to confirm
Due on receiptUse the governing anchor dateWhat event counts as receipt?
Net daysAdd a stated number of calendar daysDoes the agreement use calendar days?
End of monthMove to a month end, optionally after a cutoffDo late invoices roll into the next month?
Business daysCount only payable weekdays and supplied holidaysWhich calendar and starting convention apply?

A weekend or holiday adjustment is a separate rule applied after the base date. A term might leave the base date unchanged, move it forward to the next business day, or move it backward. That choice must come from the invoice, contract, payer policy, or applicable law; it cannot be inferred from the date alone.

The final date is therefore a documented interpretation of explicit inputs, not a legal finding. Holiday observance, local banking closures, invoice defects, acceptance disputes, grace periods, payment-processing time, and interest rules can all change the real obligation.

How to Use This Tool:

Start with the date and payment wording that actually govern the invoice rather than assuming the printed invoice date always starts the term.

  1. Enter the Invoice or anchor date, then choose the stated Payment term. For Net, EOM-plus, or business-day terms, enter the whole number of days from 0 to 3,650.
  2. Set the term-specific rule. Choose the day of next month, an EOM cutoff, or whether a payable anchor date counts as business day one only when the governing wording requires it.
  3. Select the recurring Weekend pattern, enter one holiday date per line, and choose the Final due-date adjustment. Unread or duplicate holiday lines appear as warnings and should be corrected.
  4. Set the Review date. Read the base date first, then the final due date and the remaining, due-today, or overdue status at that checkpoint.

Interpreting Results:

The Base due date shows the direct result of the selected payment term. Final due includes the chosen next-day, previous-day, or no-adjustment rule. Keep both dates in the audit trail because a moved deadline is hard to verify without its unadjusted starting point.

The review date changes only the status. A positive day count is upcoming, zero is due on the review date, and a negative count is overdue by its absolute value. Changing the review date never changes the final due date.

A clean result proves that the supplied rule set is internally consistent. Before authorizing payment, reminders, penalties, or collections, confirm the anchor event, payment wording, weekend pattern, observed holidays, and rollover rule against the governing source.

Technical Details:

The calculation uses date-only Gregorian calendar arithmetic. Dates are represented as calendar-day indexes, so time zones and daylight-saving transitions do not add or remove a day. ISO dates retain the form YYYY-MM-DD even when a different display format is selected.

Formula Core:

Each term first produces a base date. A separate adjustment function scans the supplied non-working calendar, and status is the signed difference between the final due date and review date.

dfinal=A(dbase,W,H,a) DaysUntilDue=dfinal−dreview

Here W is the selected set of recurring non-working weekdays, H is the entered holiday set, and a is none, next business day, or previous business day.

Rule Core:

Selected termBase-date rule
Due on receiptBase date equals the entered anchor date.
Net calendar daysAdd the entered day count to the anchor date.
End of monthUse the anchor month end. If the anchor day is after the cutoff, use the following month end.
EOM plus calendar daysFind the applicable month end, then add the entered calendar-day count.
Specific day of next monthUse the requested day in the next month; cap 29, 30, or 31 at that month's final day when necessary.
Business daysCount payable dates after the anchor by default. When enabled, a payable anchor counts as day one.

Business-day counting skips selected weekend weekdays and exact holiday dates. Final adjustment starts at the base date and moves one calendar day at a time in the chosen direction until it reaches a payable date. A calendar with all seven weekdays excluded is invalid for business-day terms or rollover.

Input and Boundary Rules:

  • Term days must be a whole number from 0 to 3,650; day-of-month and EOM cutoff values must be 1 to 31.
  • Holiday lines may begin with YYYY-MM-DD, YYYY/M/D, or M/D/YYYY, followed by an optional label.
  • Duplicate dates are ignored after the first entry, and unread lines do not affect the calendar.
  • Leap years use the Gregorian rule, including the century exception.
  • Business-day and rollover scans stop rather than searching beyond 25,000 calendar days.

Accuracy, Scope, and Privacy:

No public, observed, bank, or jurisdiction holiday calendar is inferred. The result also excludes interest, penalties, discounts, taxes, grace periods, invoice validity, and payment-processing time.

  • Recalculate when the accepted invoice date, receipt date, delivery date, approval date, or other governing anchor changes.
  • Confirm whether the agreement counts the anchor date and how it treats a deadline on a closure day.
  • The calculation uses the dates and rules entered in the browser and does not fetch an external holiday calendar.
  • Use the output as a planning record, not legal advice or a substitute for the contract and applicable law.

Worked Example:

Net 30 ending on a weekend

An anchor date of 2026-05-01 with Net 30 reaches a base date of 2026-05-31. With Saturday and Sunday excluded and the final rule set to next business day, the final due date becomes 2026-06-01. At a review date of 2026-05-20, 12 calendar days remain until the adjusted deadline.

References: