Form 26AS mainly shows TDS/TCS and tax payments actually reported by deductors, so it’s traditionally been the “safe” base for matching taxes paid.
AIS (Annual Information Statement) is broader — it includes more transactions (interest, securities, etc.), so it can show items that never appear in 26AS.

If they don’t match, don’t panic. Cross-verify both with your bank statements, Form 16/16A, and other records. If AIS has incorrect entries, you can submit feedback in the portal before filing.

Best approach: use 26AS to confirm taxes paid, use AIS to ensure you haven’t missed reporting income.