Preparation and Completion of Payment Vouchers

Vouchers must be made out in ink, ball pen or typewritten and must not be written in pencil. Copies must be legible, and totals must be written in ink in both words and figures. Erasures and correction fluid are prohibited. A thick horizontal line is required immediately before and after the Naira figure appearing in words; spaces are not allowed, and where the Naira figure is nil, “NIL” must be entered.

Reference: Federal Government Financial Regulations, FR 604(a)–(c)