Two schedules govern 6G: 3GPP's Release 21 ladder, and ITU-R's IMT-2030 submission window. They interlock with almost no margin.
| Quarter | Track | Milestone |
|---|---|---|
| Q2 2026 TSG#112 | SA/CT | Rel-21 timeline agreed; TR 38.914 v1.0.0 approved done |
| Q3 2026 TSG#113 | SA/CT | Rel-20 SA Stage 2 complete done |
| Q4 2026 TSG#114 | RAN | Rel-20 RAN1 functional freeze |
| Q1 2027 TSG#115 | RAN | Rel-20 RAN2/3 & RAN4-core functional freeze freeze |
| Q1 2027 TSG#115 | SA/CT | Rel-20 Stage 3 freeze · Rel-21 package and 6G work items approved (Stage 1 freeze) freeze |
| Q2 2027 TSG#116 | RAN | Rel-20 RAN4 performance |
| Q2 2027 TSG#116 | SA/CT | Rel-20 ASN.1 & OpenAPI freeze |
| Q3 2028 TSG#121 | RAN | Rel-21 RAN1 functional freeze |
| Q3 2028 TSG#121 | SA/CT | Rel-21 SA Stage 2 complete |
| Q4 2028 TSG#122 | RAN | Rel-21 RAN2/3 & RAN4-core functional freeze freeze |
| Q4 2028 TSG#122 | SA/CT | Rel-21 Stage 3 freeze freeze |
| Q1 2029 TSG#123 | SA/CT | Rel-21 ASN.1 & OpenAPI freeze |
Use the months, not the graphic
3GPP's published timeline graphic is good for structure — which track, which plenary, what
freezes together. For a date, use the month-level table below, which comes from the
"Timeline for Release 21" news item and the agreement documents RP-260868 (RAN),
SP-260595 (SA) and CP-261259 (CT), agreed 10 June 2026 at TSGs#112 in
Singapore.
| Milestone | Date |
|---|---|
| Package approval + Stage-1 freeze | March 2027 |
| Stage 2, 80% | March 2028 |
| Stage 2 freeze | June 2028 |
| Stage 3 freeze | December 2028 |
| ASN.1 / OpenAPI freeze | March 2029 |
| When | Milestone |
|---|---|
| Nov 2023 | Rec. ITU-R M.2160 approved at RA-23 — the IMT-2030 framework |
| Oct 2024 | Circular Letter 5/LCCE/115 invites candidate RIT submissions; terrestrial window "02/2027–02/2029" |
| Feb 2026 | WP5D finalises draft technical performance requirements (Doc 5/116) |
| Jun 2026 | WP5D completes draft evaluation framework guidelines (Doc 5/119) |
| Dec 2026 | Study Group 5 approval of both |
| Feb 2027 | WP5D #54 — submission window opens |
| Feb 2029 | WP5D #59 — final deadline, 1600 UTC, 12 calendar days before the meeting starts |
The interlock — our own arithmetic on verified dates
ITU-R's submission window opens February 2027, one month before 3GPP freezes Release 21 Stage 1 in March 2027. Its final deadline is February 2029, two months after Release 21 Stage 3 freezes in December 2028. That two-month gap is the entire margin in the programme.
M.2160's six usage scenarios, verbatim: immersive communication; hyper-reliable and low-latency communication; massive communication; ubiquitous connectivity; AI and communication; integrated sensing and communication.