When is day 0 for a Field Alert Report?

The day you receive the information. The 3 working days count from the next working day, and the report is due by close of business on the third.

Is the 483 response deadline a legal requirement?

No. FDA's March 2026 draft guidance recommends that establishments that choose to respond do so within 15 business days after the 483 was issued.

Does the calculator know federal holidays?

Yes, from the OPM list for 2026 to 2028, including holidays observed on a nearby weekday. For later dates it warns you and skips weekends only.

Why does a records request use calendar days?

FDA's staff manual on records requests describes the usual time in calendar days: 15, or 30 when records need translation. The date on your Form FDA 4003 governs.

Tools

FDA deadline calculator

Count the days for a Form FDA 483 response, a Field Alert Report or a records request. Weekends and federal holidays are skipped where the rule says working or business days.

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Calculator

Pick a clock and a start date

Choose a clock and a start date.

Examples: a 483 issued on 24 Sep 2026 is due 16 Oct 2026, skipping Columbus Day. A Field Alert Report with day 0 on Friday 25 Sep 2026 is due Wednesday 30 Sep 2026.

The rules

What each clock counts

Quotes and sources checked 24 Sep 2026.

“FDA recommends that those establishments that choose to respond submit their responses within 15 business days after the FDA 483 was issued.”

FDA 483 response draft guidance, page 9FDA guidance, nonbindingChecked 24 Sep 2026

“The applicant shall submit information of the following kinds about distributed drug products and articles to the FDA district office that is responsible for the facility involved within 3 working days of receipt by the applicant.”

21 CFR 314.81(b)(1)Binding US regulationChecked 24 Sep 2026

Records request

FDA usually allows 15 calendar days for records requested on a Form FDA 4003, or 30 when they need translation. The date on the request governs.

Federal holidays

The holidays the calculator skips

Observed dates from OPM: federal holidays. A holiday on a Saturday is observed the Friday before, which is why 2028's New Year's Day falls on 31 Dec 2027.

2026

1 Jan 2026
19 Jan 2026
16 Feb 2026
25 May 2026
19 Jun 2026
3 Jul 2026
7 Sep 2026
12 Oct 2026
11 Nov 2026
26 Nov 2026
25 Dec 2026

2027

1 Jan 2027
18 Jan 2027
15 Feb 2027
31 May 2027
18 Jun 2027
5 Jul 2027
6 Sep 2027
11 Oct 2027
11 Nov 2027
25 Nov 2027
24 Dec 2027

2028

31 Dec 2027
17 Jan 2028
21 Feb 2028
29 May 2028
19 Jun 2028
4 Jul 2028
4 Sep 2028
9 Oct 2028
10 Nov 2028
23 Nov 2028
25 Dec 2028

Questions

Common questions

When is day 0 for a Field Alert Report?: The day you receive the information. The 3 working days count from the next working day, and the report is due by close of business on the third.
Is the 483 response deadline a legal requirement?: No. FDA's March 2026 draft guidance recommends that establishments that choose to respond do so within 15 business days after the 483 was issued.
Does the calculator know federal holidays?: Yes, from the OPM list for 2026 to 2028, including holidays observed on a nearby weekday. For later dates it warns you and skips weekends only.
Why does a records request use calendar days?: FDA's staff manual on records requests describes the usual time in calendar days: 15, or 30 when records need translation. The date on your Form FDA 4003 governs.

See it with sample data

We show the review queue, a signed monitoring report, the audit trail review and the validation package, then answer your team's questions.