(a) Except as provided in paragraph (b), the time of filing records, briefs or other documents
required to be filed within a specified time will be the date on which they are actually received by the clerk of the reviewing court.
Rule 373.Date of Filing in Reviewing Court.
Article III. Civil Appeals Rules · Part F. Other Provisions · Last amended 2025 · Last verified July 20, 2026
In one sentenceRule 373 defines the filing date for appellate documents as the day the clerk receives them, with a mailing-date exception for parties excused from electronic filing.
Full Text of Ill. S. Ct. R. 373
(b) If received after the due date, the time of mailing, or the time of delivery to a third-party commercial carrier for delivery to the clerk within three business days, for any filing excepted from electronic filing under Rule 9(c) or exempt from electronic filing under Rule 9(d) shall be deemed the time of filing. Proof of mailing, or delivery to a third-party commercial carrier, shall be as provided in Rule 12(b).
(c) This rule also applies to a motion directed against the judgment and to the notice of appeal
filed in the trial court.
Plain-English Summary
Under Rule 373, a document is considered filed on the date the reviewing court's clerk receives it. That's the general rule for records, briefs, and other papers due within a set time.
There's an exception for parties excepted or exempt from electronic filing under Rule 9. If their document arrives after its due date, the date they mailed it, or delivered it to a third-party commercial carrier for delivery within three business days, counts as the filing date instead — as long as they can prove that mailing or delivery the way Rule 12(b) requires.
The rule reaches beyond the reviewing court, too. It also governs the filing date of a post-judgment motion or a notice of appeal filed in the trial court, so the same actual-receipt rule (and mailing exception) applies there.
Frequently Asked Questions
When is a document considered "filed" in a reviewing court?
On the date the clerk receives it, unless the mailing-date exception applies.
Who can use the mailing-date exception?
Parties who are excepted or exempt from electronic filing under Rule 9.
How does someone prove a document was mailed or delivered on a given date?
The same way required under Rule 12(b), such as an affidavit or certificate of mailing, or proof of delivery to a commercial carrier.
Does this filing-date rule apply outside the reviewing court?
Yes. It also applies to a motion directed against the judgment and to the notice of appeal filed in the trial court.
What if a document is delivered to a commercial carrier instead of mailed?
The delivery date counts as the filing date, as long as the carrier delivers the document to the clerk within three business days.
Committee Comments and Commentary
(Revised July 1, 1985)
Rule 373 was new in 1967. It was designed to make it unnecessary for counsel to make sure that briefs and other papers mailed before the filing date actually reach the reviewing court within the time limit. Receipt of the paper in the clerk’s office a day or two later will not delay the appeal. As originally adopted the rule provided that the time of mailing might be evidenced by the post mark affixed by a United States Post Office. Because of problems with the legibility of post marks, and delay in affixing them in some cases, the rule was amended in 1981 to provide for the use of affidavits of mailing or United States Postal Service certificates of mailing. The 1985 amendment regarding the recording of a filing date was intended to simplify record keeping in the appellate and supreme courts.
(December 17, 1993)
The rule is revised to make the method of proof of mailing consistent with practice under Rule 12. Reference to the notice of appeal coming within the scope of the rule is a reflection of existing law (see Harrisburg-Raleigh Airport Authority v. Department of Revenue (1989), 126 Ill. 2d 326).
(December 29, 2009)
The rules on service and filing have been revised to provide for sending documents via third- party commercial carrier. Under these rules, the term “delivery” refers to all the carrier’s standard pick-up methods, such as dropping a package in a UPS or FedEx box or with a UPS or FedEx contractor.
Amendment History
Amended January 5, 1981, effective February 1, 1981; amended July 1, 1985, effective August 1, 1985; amended December 17, 1993, effective February 1, 1994; amended December 29, 2009, effective immediately; amended September 19, 2014, eff. immediately; amended Oct. 6, 2016, eff. Nov. 1, 2016; amended June 22, 2017, eff. July 1, 2017; amended Jan. 31, 2024, eff. Feb. 1, 2024; amended Nov. 13, 2025, eff. Aug. 11, 2025, nunc pro tunc.
Source & verification. Rule text, official Committee Comments, and
amendment history are reproduced verbatim from the Illinois Supreme Court Rules,
promulgated by the Supreme Court of Illinois. Last verified July 20, 2026.
· Official source
Also known as: filing date on appealmailbox rule appellate filingproof of mailing appealnotice of appeal filing dateelectronic filing exception filing date