Invoice Due-Date and Aging Calculator

Calculate a due date under a stated counting rule, then organize your own open balances as of a chosen date. This worksheet does not infer payment terms, holiday law, enforceability or an entitlement to late fees. Use the actual contract and invoice instructions.

OPERATIONS HANDBOOK / WORKSHEET

Invoice due date and local aging list

Calculate an explicit date-count scenario, then add your own anonymous invoice records. Use dates from 1900 through 2199. A scenario is not a legal payment determination.

Editable example: October 1 plus 30 calendar days is October 31. The issue date is day zero. No example invoice is saved to your list.

Anonymous invoice label Invoice date Payment days AFTER invoice date Aging as-of date

Business-day exclusions, open balance and record status

Explicit counting rule Nonworking weekdays: 0 Sunday … 6 SaturdayComma-separated numbers; use the explicit word none if every weekday is counted. Additional nonworking dates (YYYY-MM-DD)Comma or newline separated. Blank means no additional dates entered, not that no holidays exist. Working-day exclusions explicitly reviewed Remaining OPEN balance, optionalUse balance after any partial payments, not the original invoice total. Currency label (three letters)Labels group balances separately. No exchange-rate conversion. Record status

Enter the worksheet inputs.

Use anonymous labels and your own observations. Entries remain in this open page, with no account, upload, automatic storage or messaging. Export or print before closing if you need a copy.

Calendar days: show the counting convention

The invoice date is day zero. Add the entered number of days after it, without automatically moving a weekend or holiday. October 1 plus 30 calendar days is October 31. Zero days returns the invoice date. These are date-only calculations and do not model a payment cutoff time or time zone.

QuickBooks’ net-30 explanation describes net terms in calendar days. The worksheet calculates its own examples using the explicit day-zero rule; it does not determine whether a different contract starts counting from delivery, acceptance, month-end or another event. If the actual invoice gives an agreed due date directly, keep that authoritative record rather than replacing it with a generic term.

Business days need your actual exclusions

Select business mode only for a scenario requiring that rule. Supply nonworking weekdays as 0 for Sunday through 6 for Saturday, or explicitly enter none. Enter any additional nonworking dates as YYYY-MM-DD. A blank holiday list means no extra dates were entered; it does not establish that a jurisdiction has no holidays.

The business result stays unresolved until you confirm the exclusions deliberately. Counting starts after the invoice date and skips only those entered days. It does not download a national calendar or apply a legal weekend-rollover rule. At least one working weekday is required; payment terms are limited to 3,650 whole counted days.

Build a local list from real records

Use anonymous unique invoice labels, remaining open balances and a three-letter currency label. No example record is saved automatically. Partial payments should already be removed from the balance you enter. If the balance is unknown, leave it empty; the aging summary counts that unknown separately rather than inventing a zero balance.

Open records are grouped as Current, 1–30, 31–60, 61–90 and 91+ calendar days past the calculated due date. Due today is Current. Paid and void records leave the active aging totals. Totals remain separate by currency label; there is no exchange-rate conversion or reconciliation with an accounting account.

Edit records explicitly to update them. A duplicate label is blocked to prevent silent double counting. Export the session as CSV or print the list before closing: this page has no automatic storage. The exported record includes the chosen as-of date. Formula-like text is neutralized for spreadsheet safety, but you should still review imported text and currency conventions in your own system.

Put the result in the actual workflow

The invoice setup guide covers the broader invoice and archive process. Accounts receivable software selection addresses shared ownership and system requirements; a local list cannot replace those controls.

Method and source

This is original date arithmetic and session bookkeeping from reader terms, not accounting or legal advice. It supports 200 records and dates from 1900 through 2199. Primary term reference checked October 15, 2026: QuickBooks, What is net 30?. Aging buckets are stated interface conventions, not a claim that every accounting package uses the same report settings.