Name in the cause table
Redirection to 5GCN required
Source: 3GPP TS 24.301 V20.1.0, clause 9.9.3.9, table 9.9.3.9.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
3GPP Scout / Reference / EMM causes / EMM cause #31
TS 24.301EMM cause
EMM cause #31: Redirection to 5GCN required
In plain words
The UE requests service in a PLMN where operator policy does not allow it in EPC. The network sends this cause when redirection to 5GCN is required in that situation.
Our summary of the spec text quoted below.
What the spec says
When it is used
This EMM cause is sent to the UE if it requests service in a PLMN where the UE by operator policy, is not allowed in EPC and redirection to 5GCN is required.
Source: 3GPP TS 24.301 V20.1.0, clause A.2. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24301-k10.zip in the 3GPP archive.
Same cause in 5GS (TS 24.501)
TS 24.501 defines the corresponding cause for 5GS. Its page quotes the 5GS wording.
- 5GMM cause #31 (TS 24.501)
How this page was made
3GPP Scout built this page from TS 24.301 V20.1.0 as indexed on 2026-10-15. The quotes are copied from the spec, and code checks each one against the stored text and the 3GPP archive file before publishing. The plain-words line was written by an AI model (GPT-6 Sol) and checked against the quotes by a second AI model from another company (Claude Opus 5.5). The official 3GPP text governs.