On this page, we have gathered some of the frequently asked questions about UNEX™.

What is the UNEX™ System?

The UNEX™ system was created by IPC and its members back in 1994, when it was the first common measurement tool of that size. The system has been a valuable asset since then, while being adapted to the continuous changes of the postal market in the last two decades. It measures international priority letter service performance on behalf of 36 postal operators, with test mail sent from more than 50 countries on four continents with the aim of improving and maintaining high level of quality of service in terms of transit times. UNEX™ test letters posted in one country pass through the world’s postal networks until delivered to the addressee in the destination country. All test letters contain a small semi-active or passive Radio Frequency IDentification (RFID) tag. At specific reading points in postal facilities, the RFID tag transmits its identity from the processing facility to IPC’s global RFID Network Centre in Brussels, anonymously to the postal operator involved. 

The UNEX™ System uses the transmitted data, with the date of posting and receipt reported by the panel network, to calculate the transit time between specific points in the mail pipeline, allowing postal operators to manage the international mail pipeline in accordance with their delivery commitments to customers, regulators and postal partners. Postal operators can identify where bottlenecks may occur and where corrective actions are necessary. Click here to access the UNEX service fact sheet.

UNEX™ began in 1994 with just 18 postal operators in 18 countries in Europe. Currently, there are 36 postal operators worldwide participating in the UNEX™ system. See the list of participating countries.

The results reported publicly by the UNEX™ CEN module cover international priority single-piece letter mail, ie mail which is not bulk mail or any mail that would imply constraints for the customers at posting, like for example the registration of items, minimum induction volumes, equal contents or a pre-sortation of the inducted mail.

In Europe a regulatory framework drives the measurement and results reporting. The UNEX™ CEN module design complies with the CEN standard EN13850:2020 Postal Services – Quality of Service – Measurement of the transit time of end-to-end services for single piece priority and first class mail that specifies the methodology for monitoring of quality of service in the European Union (www.cen.eu)/(www.europa.eu). Clear objectives were also set by the European Postal Directive of 1997 to have 85% of the cross-border priority letter mail to be delivered within 3 days of posting and 97% within 5 days.

All parties who use UNEX™ respect the integrity of the results provided by IPC measurement. The validity and independence of the data is guaranteed by external panel recruitment and management contractors. From 2022 onward, Kantar (United Kingdom) is the sole provider for UNEX™ panel and test mail production. 

Back to top

What are the key principles of the UNEX™ measurement?

  • International end-to-end measurement, ie from a sender in the country of posting to the final addressee in the country of destination
  • Test mail produced to mirror real mail patterns sent and received by panellists
  • Independent by external contractors for panel recruitment and management chosen following the EU procurement procedures
  • Continuous throughout the year from January to December
  • Priority letter mail
  • RFID diagnostic
  • High-level and in-depth controls of quality of data

Back to top

How does the UNEX™ system work?

The UNEX™ system is based on a network of anonymous volunteer ‘panellists’ – currently over 5,800 individuals worldwide – who send and receive test letters according to a weekly plan, and who enter the posting or delivery time on a central computer system. Over 350,000 international first-class/priority mail test letters (envelopes and untracked small packages) are sent and monitored each year in the system in total. Test letters mirror real mail geographical patterns in the country of origin as well as in the country of destination. These letters are produced to also adhere to other real mail characteristics such as the sending modes through panellist profiles (letter box, post office, collection at business premises) or franking modes (stamp, meter, PP), sizes (envelopes C6, C5, C4 and small packets) or weights (20g, 50g for envelopes and ca 125g for small packets). The test letters move anonymously through the international mail-processing system, from posting through delivery to the final addressee.

Back to top

Can you tell me a bit more about the Radio Frequency IDentification (RFID) Technology used in the UNEX™ system?

All UNEX™ test mail contains an RFID device, so that – as the test item moves through the mail pipeline – the time of its arrival at specific points can be recorded automatically by radio receivers located in postal facilities. These radio receivers are linked to a global RFID Network run by International Post Corporation. In a fully anonymous manner, they help to identify any delays which may occur along the postal process, from origin country to destination country. This RFID technology, with continuous technical enhancements, has been in use for the UNEX™ postal quality of service measurement for more than 25 years. Currently IPC's RFID network serves 28 postal operators and more than 150  postal facilities with ca. 2200 reading points.

Once the RFID-transmitted data is sent to IPC’s global RFID Network Centre, the system identifies the progress or delays of the test letter from the sender in the origin country to the addressee in the destination country. UNEX™ provides measures on both end-to-end and domestic segments of the international mail pipeline, including transport.

Back to top

Why does the UNEX™ CEN module results brochure not show a figure for all pairs of European countries measured?

It can be due to the fact that the real mail volume on such country-to-country links is very small or it can be due to the fact that there is not one unique postal operator in charge of the universal postal service obligation in a specific country.

Indeed, the UNEX™ CEN module design applies the requirements of the EN13850:2020 CEN standard on Postal Services – Quality of Service – Measurement of the transit time of end-to-end services for single piece priority and first class mail. In that standard provision was made for the very small flows defined as carrying real mail volumes below 11,500 mail pieces per year. These flows can be excluded from the measurement as the simple fact to add test mail on such flows would increase their real mail volume by more than 2.5%, thus artificially boosting the real volume that would be used to calculate the statistical design and bringing no added value.

Secondly, this standard is not applicable for the measurement of end-to-end transit times in Multi-Operator Environments where there is not a unique universal postal service for single-piece mail. That is why the flows from Germany are measured on a voluntary basis, upon request of other postal operators than Deutsche Post DHL Group.

This EN13850:2020 standard is not applicable either for the measurement of end-to-end transit times of bulk mailers’ services and hybrid mail, which require different measurement systems and methodologies ie the UNEX™ results are in no way reflecting the performance of such mail products.

Back to top

The performances shown in the UNEX™ CEN module results brochure do not mirror at all my personal experience of customer sending international mail!

Please note that the UNEX™ CEN module results relate precisely to international priority single-piece letter mail only and are not meant to be representative of any other mail product selected by a customer.

In particular this means that the UNEX™ CEN module results do not represent the service levels provided by postal operators for:

  • envelopes bigger than C6, C5 or C4 formats, thicker than 2mm thick, nor does it represent small packets or parcels;
  • economy mail, as UNEX™ measures priority mail also known as – depending on the country – ‘1st class’, ‘Airmail’, ‘Luftpost’, ‘Prioritär’, ‘A Prioritaire’ and which in most cases must carry a blue sticker indicating that service choice, or
  • registered mail; whereas priority letter service is about speed of delivery, registered mail is about making sure that it arrives at the final addressee and getting a proof of this. That option is often chosen for mailing valuable goods, purchases or important document requiring the signature of the recipient and special safety measures to keep that mail at the various locations in the postal pipeline from one country to another.

Back to top

What does the UNEX™ acronym stands for?

It stands for UNipost EXternal where ‘Unipost’ was the name in 1994 of the IPC section covering other topics than operations and technology and where ‘External’ underlined the independence of the measurement from the postal operators measured.

Back to top