Short answer. Ten calendar days from notice of the order, unless the court fixes a different period. Section 3 of Rule 12 also allows the bill of particulars (or more definite statement) to be filed either separately or as an amended pleading, served on the adverse party.

What the law says

If the motion is granted, either in whole or in part, the compliance therewith must be effected within ten calendar days from notice of the order, unless a different period is fixed by the court. The bill of particulars or a more definite statement ordered by the court may be filed either in a separate or in an amended pleading, serving a copy thereof on the adverse party.

Rule 12, Section 3 — Compliance with order. Read the full provision →

The default ten-day compliance window

Section 3 sets the timeframe for compliance once a motion for a bill of particulars is granted, in whole or in part: the compliance therewith must be effected within ten calendar days from notice of the order, unless a different period is fixed by the court. As with several other deadlines in the Rules, ten calendar days is the default, but the court retains discretion to set a different period suited to the circumstances of the case. This default period gives the responding party enough time to gather the additional facts or clarify the allegations the court found wanting, while still keeping the case moving rather than leaving the bill of particulars open-ended with no deadline at all.

Two ways to comply: separate or amended filing

Section 3 gives the responding party a choice in how to actually provide the bill of particulars: it may be filed either in a separate or in an amended pleading. A party can submit the more definite statement as its own standalone document responding to the order, or fold it into an amended version of the original pleading — either approach satisfies the requirement, so long as it is done within the applicable deadline.

Service on the adverse party is still required

Whichever format is chosen, Section 3 requires serving a copy thereof on the adverse party — the bill of particulars is not simply filed with the court and left there; the opposing party must actually receive a copy. This ensures the party who moved for the bill of particulars gets the clarified, more definite information they sought, which is the whole point of having made the motion in the first place. Skipping service on the adverse party, even if the bill of particulars is properly filed with the court, would defeat the purpose of the order, since the opposing party would have no way of knowing that the vague or missing details had actually been supplied.

Related provisions

Note. Statute text quoted on this page is reproduced from the official enactment and is linked to the full provision. The explanation around it is general legal information from Vivas & Nobles Law Office, not legal advice. Whether it applies to your situation depends on facts only a lawyer reviewing them can assess.