Missouri discovery deadlines: 30 days, and a 45-day floor that appearing can start early

Missouri uses 30 days across all three written discovery devices. A defendant gets a 45-day floor on top of that, and the way it is measured is unusual: from the earlier of entering an appearance or being served with process.

That word "earlier" is the one to notice. Appearing promptly, which is otherwise good practice, starts the 45 days running sooner.

The three deadlines

Interrogatories

Mo. Sup. Ct. R. 57.01(b)(1):

When the Response Is Due. Responses shall be served within 30 days after the service of the interrogatories. A defendant, however, shall not be required to respond to interrogatories before the expiration of 45 days after the earlier of: (A) The date the defendant enters an appearance, or (B) The date the defendant is served with process. The court may allow a shorter or longer time.

Read the structure carefully, because it is not an extension.

The 45 days is a floor, not an addition. A defendant is not required to respond before it expires. Once it has expired, the ordinary 30 days governs.

And it runs from the earlier of two dates. Most rules that combine two triggers take the later one, which favors the responding party. Missouri takes the earlier, which does not.

The practical consequence is worth stating plainly: if you enter an appearance before you are formally served, your 45-day floor begins on the appearance date rather than the service date. That does not make appearing a mistake — there are good reasons to appear — but it does mean the floor is shorter than a defendant might assume.

Rule 57.01(b)(2) adds a formatting requirement: the title of the response shall identify the interrogatories being answered, so a response has to be labeled to match.

Document requests

Mo. Sup. Ct. R. 58.01(b)(1):

When Response Is Due. Responses shall be served within 30 days after the service of the request. A defendant, however, shall not be required to respond to the request before the expiration of 45 days after the earlier of: (A) The date the defendant enters an appearance; or (B) The date the defendant is served with process. The court may allow a shorter or longer time.

Identical structure, identical floor, identical measuring point.

Requests for admission: 30 days, capped at 25

Mo. Sup. Ct. R. 59.01(a) carries a limit that the other two rules do not:

After commencement of an action, a party may serve upon any other party no more than 25 written requests for the admission, without leave of court or stipulation of the parties, for purposes of the pending action only, of the truth of any matters within the scope of Rule 56.01(b) set forth in the request that relate to statements or opinions of fact or of the application of law to fact, including the genuineness or foundation of any documents described in the request.

Twenty-five, absent leave or a stipulation. If you have received more than that and no order or agreement permits it, that is worth raising before you answer them all.

Rule 59.01(b)(1):

When Response Is Due. Responses shall be served within 30 days after the service of the requests for admissions.

Admissions carry no 45-day defendant floor. They run on 30 days from service, full stop — which makes them the shortest of the three periods for a defendant early in a case, and the one to calendar first.

One version note. The text of Rule 59.01 on this site is marked effective until January 1, 2027, so there is a later version taking effect on that date. If you are reading this close to or after that date, check the current text before relying on the numbers here.

What to do when the deadline is tight

Work out your floor first if you are a defendant. Take 45 days from whichever came earlier — your appearance or service of process — and compare it to 30 days from the request. You owe the later of the two, and only for interrogatories and document requests.

Remember admissions have no floor. Thirty days from service, and the consequences of missing them are the harshest of the three.

Ask the court. Rules 57.01 and 58.01 both say the court may allow a shorter or longer time, and asking before the period runs is treated far more generously than explaining after.

Answer what you can and object specifically to the rest. A timely partial response preserves your position; a late complete one does not.

Rule 61.01 supplies the sanctions machinery for a failure to make discovery, with consequences that escalate.

How Missouri compares

A short checklist

1. Calendar 30 days for all three devices as your starting point.
2. If you are the defendant, compute the 45-day floor — from the earlier of your appearance and service of process, not the later.
3. Compare the two and take the later date for interrogatories and document requests.
4. Do not apply the floor to admissions. They run on 30 days from service with no defendant's period.
5. Count the requests for admission. More than 25 requires leave of court or a stipulation.
6. Title your responses to identify the request being answered, as Rules 57.01 and 58.01 require.
7. Ask the court for more time before the period expires, not after.
8. Check the version date on Rule 59.01 — the current text runs until January 1, 2027.

Where these rules live

• Mo. Sup. Ct. R. 56.01 — General Provision Governing Discovery
• Mo. Sup. Ct. R. 57.01 — Interrogatories to Parties
• Mo. Sup. Ct. R. 58.01 — Production of Documents and Things and Entry Upon Land
• Mo. Sup. Ct. R. 59.01 — Request for and Effect of Admissions
• Mo. Sup. Ct. R. 61.01 — Failure to Make Discovery: Sanctions

This page explains what the rules say. It isn't legal advice, and the discovery cut-off in any particular case is set by the court's scheduling order rather than by the rules reproduced here.