Simplified Involuntary Reroute Settlement

Bills should be paid for, not disputed.

Why SIRS?The ProcessFAQFeesJoin

Receiving carriers are entitled to bill issuing carriers for involuntary reroute tickets for the lowest applicable published fare. That explains the over 5 million rejection memos sent every year for involuntary reroutes alone. Stop disputing and start settling with Simplified Involuntary Reroute Settlement (SIRS) by ACH.


The current process is complex.

If original ticket was 1) not an applicable fare based on the published fare basis of the ticket or 2) not filed in a tariff available to the general public, the receiving carrier is entitled to bill the issuing carrier the lowest applicable published fare. This leads to disputes.

A simpler, fair fare.

With ACH’s SIRS, participating airlines settle involuntary reroutes at a percentage of the IATA Weighted Mileage Factor (WMF) based on origin and destination of the lifted involuntary reroute coupon or FIM. Eliminate lengthy rejection stages with SIRS by ACH.

How It Works

Samples Taken

We take a 1% sample of participating carriers’ sales and retrieve each coupon’s MPA prorate amount and IATA WMF.

Rate Calculated

Results are separated into 8 global regions based on O & D. Rate = MPA prorate divided by IATA MWF.

Applied to Segment(s)

Based on the clearance month and global region, the settlement rate is taken and applied to the WMF of a given segment.

Frequently Asked Questions

Who should join?

Any airline that would like to settle involuntary reroutes with a simple, fast, fair and dispute free method.

How can I tell if my interline partner is a member of SIRS?

Check out our Multilateral Matrix of signatories.

How are monthly rates established?

Monthly settlement percentage rates for each of the 8 global regions are established by dividing
the MPA prorate amount by the IATA weighted mileage factor of each coupon from 1% of sales
issued by Parties that have authorized its sales to be included in the calculation. Specific sales
transactions are excluded from the calculation as defined in the Agreement.

Does this supersede existing bilateral agreements?

No. Bilateral Agreements specifying terms of settlement of involuntary reroute tickets and FIMs
between two Concurring Parties supersede the terms of this Agreement unless otherwise agreed
between the two Parties.


$1,500.00Billed annually

How to Join

  1. Complete and execute the SIRS Agreement
  2. Send the executed agreement to
  3. Execute the concurrence agreement in appendix D with other SIRS parties