EDIFACT message guide · Travel and tourism

RESMSG Reservation

The UN/EDIFACT message a tourism operator sends to service providers to request services such as accommodation, subject to confirmation.

Sent by
Tour operator
Received by
Hotel, transport company or other service provider
Standard
UN/EDIFACT · Batch message
X12 equivalent
No direct equivalent

What is the EDIFACT RESMSG message?

RESMSG is the UN/EDIFACT reservation message. The directory defines it as a message sent by a tourism operator to one or more service providers to request desired services, which may be subject to confirmation by any of the parties concerned.

Tour operators build packages from rooms, transfers and excursions supplied by many providers. The reservation tells each provider the guests, dates, room or service types and any special requests. Providers reply with a supplier response (SUPRES), confirming, changing or declining the request, so the operator knows each part of the package is secured.

How the EDIFACT RESMSG message worksDiagram of the UN/EDIFACT RESMSG Reservation message. Tour operator sends it to hotel, transport company or other service provider. It usually starts the exchange. It is usually followed by SUPRES. Inside the UNB and UNH envelopes, the directory D.21A requires, in the start of message: BGM (Beginning of message). 3 conditional segment groups are listed by their trigger segment.How the EDIFACT RESMSG message worksReservation: who sends it, where it fits and what the directory marks mandatory1 WHERE IT FITSUSUALLY FOLLOWSStarts the exchangeRESMSGSENDERTour operatorRECEIVERHotel, transportcompany or otherservice providerCONTRL syntax report back, if agreedUSUALLY FOLLOWED BYSUPRESSupplier response2 WHAT DIRECTORY D.21A REQUIRESInterchange: sender and recipient IDsUNB … UNZMessage RESMSGUNH … UNTSTART OF MESSAGEBGMBeginning of messageBODY AND SEGMENT GROUPS+ 3 conditional groups, starting with:RFFNADSEQBlue box: mandatory segment group. Conditional groups are listed by the trigger segment that starts them; a group is sent only when its data applies.Conditional segments outside groups are not drawn.Structure: mandatory segments and groups in the UN/EDIFACT directory D.21A listing for RESMSG. Your trading partner's implementation guide adds itsown requirements.
How the EDIFACT RESMSG message worksDiagram of the UN/EDIFACT RESMSG Reservation message. Tour operator sends it to hotel, transport company or other service provider. It usually starts the exchange. It is usually followed by SUPRES. Inside the UNB and UNH envelopes, the directory D.21A requires, in the start of message: BGM (Beginning of message). 3 conditional segment groups are listed by their trigger segment.How the EDIFACT RESMSGmessage worksReservation: who sends it, where it fits andwhat the directory marks mandatory1 WHERE IT FITSUSUALLY FOLLOWSStarts the exchangeRESMSGSENDERTour operatorRECEIVERHotel, transportcompany orother serviceproviderCONTRL syntax report back, if agreedUSUALLY FOLLOWED BYSUPRESSupplier response2 WHAT DIRECTORY D.21A REQUIRESInterchange: sender and recipient IDs(UNB … UNZ)Message RESMSG (UNH … UNT)START OF MESSAGEBGMBeginning of messageBODY AND SEGMENT GROUPS+ 3 conditional groups, starting with:RFFNADSEQBlue box: mandatory segment group. Conditionalgroups are listed by the trigger segment thatstarts them; a group is sent only when its dataapplies. Conditional segments outside groups arenot drawn.Structure: mandatory segments and groups in theUN/EDIFACT directory D.21A listing for RESMSG.Your trading partner's implementation guide adds itsown requirements.

How to read this diagram: the top row shows who sends RESMSG, to whom, and which messages usually come before and after it. The lower part shows what the directory D.21A itself requires: the envelopes around RESMSG and the segments and segment groups it marks mandatory. Conditional groups are listed by their trigger segment rather than drawn in full. This is the directory's minimum, not a trading partner's requirement: a message implementation guide, such as an industry subset or a partner’s own guide, usually makes some conditional groups mandatory, restricts the codes and may use an older directory.

Expand diagram Download SVG

When it is used

  • Booking hotel rooms for package holidays
  • Reserving transfers and excursions
  • Changing or cancelling reservations

Where it fits in the message flow

This message RESMSG Reservation
Usually followed by SUPRES Supplier response

Structure

Mandatory segments in RESMSG (directory D.21A)

In UN/EDIFACT directory D.21A, the RESMSG message has 65 segment positions arranged in 14 segment groups. These are the segments and segment groups marked mandatory at message level, in order; a mandatory group is shown with the segment that starts it. Segments inside conditional groups are needed only when the group is used. This is the directory’s requirement, not your trading partner’s: each partner’s message implementation guide names the directory it uses, often an older one such as D.96A or D.01B where the structure can differ, makes some conditional segments mandatory and restricts the codes.

  • UNH
  • BGM
  • UNT

Practical example

RESMSG in practice

A tour operator sells a week's holiday for a family of four. Its reservation system sends the hotel a RESMSG with the guest names, arrival and departure dates, a family room on half board and a request for a cot. The hotel confirms the booking with a SUPRES, and the operator issues travel documents.

Implementation

Implementation considerations for RESMSG

  • Use the room and service codes agreed with each provider.
  • Track every reservation until it is confirmed.
  • Send changes and cancellations promptly to avoid charges.
  • Protect guests' personal data under applicable law.

Need help with RESMSG?

ECOM maps, tests and monitors EDIFACT messages for your trading partners and integrates them with your ERP.