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FAQ - Frequently Asked Questions


Who is eligible to join?

    Any airline is eligible to join SIS, whether or not they are a member of a clearing house, though participation is most beneficial if the airline is involved in interline carriage. Non-airlines may also join SIS provided that they do business with airlines. It is not possible for non-airlines to do business with other non-airlines through SIS.

What is required to join SIS?

    For an airline, to have a current 2 alpha or 2 alpha-numeric designator and 3 numeric accounting code/prefix, e.g. AA-001. For a non-airline, to be a registered company evidenced by a corporate registration and copy of the audited accounts. An XB designator and alpha-numeric accounting code (e.g. XB-C44) will be issued by the IATA Clearing House to enable non-airline participation in SIS.

How do I join SIS?

    Access to SIS is granted once the Integrated Settlement Participation Agreement has been signed and the participant has passed the necessary certification process. This process is detailed in the Sign-Up Guide. These documents will be made available in the Materials section of the website.

Do I need to join SIS if I am already an ICH member?

    Yes. ICH membership does not automatically grant a participant the access to SIS. Membership to SIS will be granted after the IS Participation Agreement is signed.

Will my membership at the ICH be terminated if I do not join SIS?

    No. However, by April 2013, access to the IATA Clearing House will be discontinued, which means at this time the ICH-WEB interface will no longer be in service. Essentially, if you are an ICH Member, you will be required to submit invoices through SIS after April 2013 at the latest.

    For more information on this topic, please review the Key Dates section, which outlines the key milestones from the current process and the migration to SIS. We would also recommend reviewing the pages of About SIS for more information on the project.

I do not know anything about SIS, Where can I start?

    A good starting point would be a brief overview about what SIS is and the benefits it provides – this can be found in the About SIS section of the website. Interline billing and revenue accounting managers can also start by reviewing the Integrated Settlement Participation Guide (ISPG) document, which provides the necessary information and specifications needed to fully implement SIS.

How do I know when my interline partners are migrating to SIS?

    Airlines’ migration plans will be shared on a permission-basis. In the SIS Forums, there is a designated place where planned migration dates of airlines are stored. This information is released to the parties that are willing to share their own migration plans with us and their fellow carriers that have access to the list. For more information regarding this, please email us at

I have reviewed the documents but do not understand some concepts – where can I ask questions regarding SIS?

    If you have reviewed the various SIS documents (Airline Business Case, Integrated Settlement Participation Guide, industry presentations, etc.) and would like clarification on specific topics, you may be able to find your questions already answered on the SIS Forum. If not, you may also post your question there and someone from the SIS Team will reply.

What is the purpose of the SIS Forum?

    The SIS Forum is a collaborative platform where the industry can post questions and exchange knowledge/ideas about SIS.

What are the charges of using SIS?

    SIS is run on a cost-recovery basis. These charges will also be specified in the Integrated Settlement Participation Agreement.

What are the key dates for SIS?

    Sept 2011         Passenger & Miscellaneous go-live (release 1.0)

    Apr 2012           Cargo & UATP go-live (release 1.1)

    A complete table outlining the Key Dates for SIS can be found in the Key Dates section of the website. 


    Signing Up & Migration Steps

    What are the key submission options for SIS?

      One of the many benefits of SIS is that interline partners will no longer depend on each other when it comes to choosing the formats to submit files. Under SIS, participants may select among various formats to submit files and this will not affect the way their billed entities receive the files.

      The three submission options are IS-IDEC, IS-XML, and IS WEB (manual input via web interface).

      A matrix outlining the possible options to submit files/invoices can be found in the Integrated Settlement Participation Guide (ISPG) Chapter 2.3.

    What is the Sandbox?

      The Sandbox is a dedicated separate environment primarily having the IS validation components. The purpose of the Sandbox is to ensure that the outputs generated by your individual revenue accounting systems are as per the requirements of IS.

      In the Sandbox, you will be able to upload IS format files (IS-IDEC and IS-XML) without any restriction on the number of files. SIS will validate your input file (IS-Validation) and will also check if the minimum certification requirements are met. Further details on the Sandbox are specified in the Sign-Up Guide. 

    How can I learn about using SIS?

      Various training materials will be made available prior to go-live. These include:

      a.     Computer-Based-Training (CBT)

      b.    User Manual

      Information on these materials will be described on the Materials page.

    If I am not migrated, how do I respond to the invoices submitted by my partner via SIS?

      According to the Revenue Accounting Manual (RAM) rules (ref. RAM A10, part 2), if an airline receives a Prime billing or rejection or correspondence that was submitted via SIS, and it wishes to dispute that billing, rejection or correspondence, it has to do so via SIS. This is applicable to all billing categories (Passenger, Cargo, Miscellaneous, and UATP after the respective SIS implementation).

      As this is not yet made explicit in the RAM for Miscellaneous and UATP, the RAM will be revised later this year to include this provision. So in summary, as a non-migrated carrier, you will use SIS (IS-WEB) at the latest from September 2011 onwards for Passenger and Miscellaneous rejections and correspondence.

    Once I have started my migration, can rejections and correspondence be done in SIS on invoices that have been submitted prior to the migration period?

      Yes. However, once a transaction is in the migrated track, it has to stay there.

    When will I stop receiving paper invoices from my interline partners?

      You may stop receiving paper invoices three (3) months after your interline partner has started submitting invoices in SIS. It is also possible to have bilateral agreements that specify for an earlier or later removal.

    When can I view/modify my Member Profile?

      Prior to go-live, participants may view/modify their Member Profiles in the Sandbox. This information will then be moved to the Production system once SIS goes live. After the go-live date, participants will do their Member Profile updates in the production environment only.

    Will my ICH Form 1 (F1) and Form 1 Report From Debtor (F1FD) contain billing information from both migrated and non-migrated entities?

        Both the F1 and the F1FD will show the origin of the invoices, so whether from ICH Web or SIS, you will be able to see where the data that contributes to the Form 3 balance originated.


      Technical Aspects

      If a non-migrated entity send an old IDEC file to a migrated carrier, how will the migrated entity receive the file?

        non-migrated billing carrier continues with the current process and sends the (old) IDEC to ATPCO. ATPCO is switching this (old IDEC) File to the migrated billed carrier.

        The migrated billed carrier, therefore, cannot receive an IS-IDEC – as many fields/information would be missing. Hence, a migrated billed carrier must be able (until Sep 2012 –when old IDEC is discontinued) to process an incoming old IDEC as well as the new SIS Formats IS-IDEC or IS-XML (at their choice).

      Can I view invoices submitted via all formats (IS-XML, IS-IDEC, and IS-Web) on the IS Platform?

        Yes. SIS offers the flexibility for all invoices submitted in any format to be viewed in IS-Web. Please also refer to the ISPG Chapter 2.3 for more information on the overall flexibility of file transmission choices.

      Can formats of invoices be mixed? e.g. IS-XML for one Charge Code and IS-Web for another Charge Code?


      Do Account Receivables (AR) and Account Payables (AP) need to both be migrated at the same time?

        No. While we expect and encourage everyone to migrate both AP and AR at the same time, we will not be enforcing this rule. However, this will be reviewed by the SIS governing and industry bodies as needed to ensure that the industry is not aggrieved by this.

      Will there be a duplicate check for invoices submitted through SIS and through the ICH (by F12) at the same time?

        Yes. First, a warning message at time of submission will alert the user that duplicate invoices are identified as compared to SIS invoices previously received.

        Secondly, a duplicate check (performed by the ICH) is done by ICH Operations, rather than as an automated process done by the system without human intervention. The ICH system will flag all potential duplicates, highlighting those which are perfect duplicates and those which are partial duplicates. Perfect duplicates (all data criteria match) will be reviewed by ICH Operations, and unless there is some human-discernable reason for doubt, the ICH Web versions of the duplicates will all be deleted. An email will automatically be sent to the creditor advising of the deletion. Near-perfect duplicates (many data criteria match, but not all) will not be deleted, but will be queried with the creditor by ICH Operations.

        Note: Warning alert will be issued when duplicate invoices numbers are identified in the case that F12 is sent after the SIS invoices submission (works only in this order).

      How will the Call Day Adjustments (CDA) operate with SIS?

        The ICH will generate CDA invoices as now and will create an IS-XML file (Charge Category: Service Provider / Charge Code: CDA) on the initialization of Clearance Period 2. Additional to today, the IS-XML file will also provide details of original invoices included in the CDA to simplify reconciliation of CDA amounts and enable allocation of any adjustment to the original invoices. As the invoice number format used by the ICH today exceeds the number of characters available in SIS, the number format will be changed to: "CD" + YY (invoice year) + MM (invoice month) + XXXX (incremental number), e.g. CD10080023 would identify the 23rd CDA invoice generated for August 2010.

      What are the costs associated with using iiNet?

        For the basic file transfer functionalities to/from SIS, no transaction fees will be applied. The access to iiNet using a manual account will also be free of charge. Participants wishing to set up a new automated file transfer account would be charged the current iiNet on time fees. Any optional iiNet functionalities beyond the basic file transfer, will be subject to iiNet current fees.


      Additional information

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