Keeping the records

A record is kept for as long as someone may need to check what it supports. For tax, that's the period in which the IRS can assess more tax or the company can claim a refund. That period has a length, and it starts on a date you can work out.

If Northwind files its 2026 return on its due date, April 15, 2027, the records behind it are kept at least until April 15, 2030. The third quarter's payroll records count from the later of the deposit and the return, November 2, 2026, so they stay until at least November 2, 2030. The van's purchase invoice is kept for as long as the van is depreciated and until the period runs out for the year it's sold, which is likely to be the longest-kept record in the first month's book.

Keeping a record means being able to find it. A receipt attached to the transaction in the books is a record. A receipt somewhere in a founder's email is not. The audit trailControlsAudit trailThe immutable record of every state change is the books plus the evidenceControlsEvidenceDocumentation supporting a recorded amount behind each entry, kept together for the whole periodCore ledgerPeriodA fiscal reporting window someone may ask.

Receipts live in inboxes, and the old bank exports are deleted once the return is filed.

Every receipt is attached to its transaction when it's coded. Each closed year is archived with its return, and nothing is deleted before its period ends.

Where this goes next: Closing the monthAccounting · Lesson 13 of 17Closing the monthWhat does it mean to close the books for a month?The close proves every balance against something outside the ledger, then locks the period so the numbers can't change after sign-off.10 min · 2 pages shows the evidence behind each balance, the R&D credit's recordsR&D tax credit · Lesson 8 of 9Records, amended claims and state creditsWhat documentation do I need for the R&D tax credit, and can I claim a past year?The records a credit stands on, what an amended-return claim must contain, which elections it can't make, and where state credits come in.9 min are the strictest a startup keeps, and fixed assets and depreciationAccounting · Lesson 16 of 17Fixed assets and depreciationWhen should a startup capitalize a purchase, and how does depreciation work?A capitalization policy, two October purchases on either side of it, the van's schedule over its whole life, and what selling it does to the books.9 min · 2 pages is where the van's records come from.