Uzbekistan: new ICAO codes, new transition levels

Some big changes came into effect in Uzbekistan on October 2. The country has officially dropped its old “UT” ICAO prefix in favor of “UZ”.

So the Tashkent FIR is now UZTR (was UTTR), and the Samarkand FIR is now UZSD (was UTSD). The same applies to all airports: Tashkent becomes UZTT, Samarkand is now UZSS, Bukhara is UZSB, and so on.

According to UzAeroNavigation, the national ANSP, this is part of a wider modernization effort – giving Uzbekistan’s airspace a clearer, more distinct identity and moving away from the legacy Soviet-era “UT” codes.

Click for PDF from AIP.

At the same time, Uzbekistan has introduced a unified transition altitude of 13,000 ft and transition level of FL150 (previously 6,000 ft / FL080), bringing it more in line with its Central Asian neighbors and hopefully making level changes at FIR boundaries a bit smoother.

The higher setting means crews will stay on local pressure a bit longer when climbing out from airports like UZTT/Tashkent and UZSS/Samarkand, which sit close to mountainous terrain – helping with altitude awareness until they’re well clear.

Uzbekistan handles a steady stream of east-west overflights linking Europe with China, Hong Kong, South Korea, and Japan. These routes have become even more important since 2022, as many operators continue to avoid Russian airspace, routing instead through Kazakhstan, Uzbekistan, and Turkmenistan on their way to and from Asia.

One important heads-up: the new “UZ” ICAO addresses have been published, but they’re not active for flight plan filing yet.

For now, keep using the old “UT” AFTN addresses for everything — flight plans, messages, permits, and so on. For example, file to UTTRZQZX for the Tashkent FIR (not UZTRZQZX).

According to UZTR Notam D0922/25, the switch to the new addresses won’t take effect until 29 Oct 2025, so stick with the old ones until then (or until further notice).

2 Comments

ANil Rana says:

7 October, 2025 at 9:54 am

Hi David,

Just a quick update — the new ICAO addresses for airports and FIRs are not yet valid. Although the addresses have changed, we still need to file using the old ones.

For example, FIR UZTR should continue to be filed to UTTRZQZX, and the same applies to other FIRs / ADs / overflights etc. / as well.

Please continue using the old addresses until 29 October 2025. For reference, see NOTAM UTTT D0922/25.

D0922/25 NOTAMN
Q)UTXX/QAFXX/IV/NBO/E/000/999/4251N06428E394
A)UTTR UTSD B)2510020000 C)2510292359
E)ALL OPERATIONAL REQUESTS AND CORRESPONDENCE(INCLUDING FLIGHT PLAN,
CHG,CNL,DEP/ARR,DLA,RQP/RQS,SLOT/CTOP,OVERFLIGHT PERMITS,NOTAM
REQUESTS,AIS/OPS QUERIES)SHALL BE ADDRESSED TO AFTN ADDRESSES WITH
PREFIX ‘UT'(E.G.UTTTZDZX-ATFMU,UTTTYOYX-AIS/NOTAM).
EFFECTIVE 02 OCT 2025 00:01 UTC UNTIL 29 OCT 2025 23:59 UTC OR UNTIL
FURTHER NOTICE.
REF: AIRAC AMDT 05/25,EFFECTIVE DATE 02 OCT 2025.

- David Mumford says:
  
  8 October, 2025 at 8:40 am
  
  Thanks for the info! I’ve incorporated this into the article now!

Uzbekistan: new ICAO codes, new transition levels