Treasury Regulations (26 C.F.R.)
26 CFR § 40.6151(a)-1 — (a)-1 Time and place for paying tax shown on return.
Except as provided by statute, the tax must be paid at the time prescribed in § 40.6071(a)-1 for filing the return, and at the place prescribed in § 40.6091-1 for filing the return.
Source: official text