Q.A bill of exchange is dated 15th January 2026 and is drawn payable 'three months after date'.

The due date needs the nominal term counted first, then three days of grace added, and finally checked against any declared holiday on that date.

Step 1 — Nominal due date. The bill is drawn for a period stated in months ('three months after date'), so the nominal due date falls on the corresponding calendar date three months after 15th January 2026, which is 15th April 2026.

Step 2 — Add three days of grace (Section 22, Negotiable Instruments Act, 1881). Since the bill is not payable on demand, three extra days are added: 15th April 2026 + 3 days = 18th April 2026. This is the bill's actual due date (date of maturity).

Step 3 — Public holiday adjustment (Section 25). If 18th April 2026 is declared, in advance, a public holiday, the bill matures instead on the preceding business day, i.e. 17th April 2026. (Had 18th April instead turned out to be a sudden, unforeseen/emergency holiday declared after the due date was already fixed, the rule would work the other way — the bill would mature on the next business day instead.)

Forgetting to add the three days of grace at all; applying the 'preceding business day' rule even for a sudden/emergency holiday, where the correct rule instead moves the due date forward, not back.