Timer value
Default 54 min NOTE 1 NOTE 2
Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.
3GPP Scout / Reference / 5GS NAS timers / T3512
TS 24.501NAS timer
Timer T3512: 5GS mobility management, UE side
In plain words
In 5GMM-REGISTERED, the UE starts T3512 on leaving 5GMM-CONNECTED mode without indicated strictly periodic registration timer support and restarts it on expiry in 5GMM-CONNECTED mode.
Our summary of the spec text quoted below.
What the spec says
Started when
In 5GMM-REGISTERED, when 5GMM-CONNECTED mode is left and if the NW does not indicate support for strictly periodic registration timer as specified in clause 5.3.7. If the network indicates support for strictly periodic registration timer, T3512 is started after the successful completion of registration update procedure. [...]
Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.
Stopped when
When entering state 5GMM-DEREGISTERED When entering 5GMM-CONNECTED mode if the NW does not indicate support for strictly periodic registration timer as specified in clause 5.3.7.
Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.
On expiry
In 5GMM-IDLE mode, Initiation of the periodic registration procedure if the UE is not registered for emergency services. In 5GMM-CONNECTED mode, restart the timer T3512. Locally deregister if the UE is registered for emergency services
Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.
State
5GMM-REGISTERED
Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.
Note 1 of the table
NOTE 1: The value of this timer is provided by the network operator during the registration procedure.
Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.
Note 2 of the table
NOTE 2: The default value of this timer is used if the network does not indicate a value in [...]
Source: 3GPP TS 24.501 V20.1.0, clause 10.2, table 10.2.1. © 3GPP Organizational Partners (ARIB, ATIS, CCSA, ETSI, TSDSI, TTA, TTC). Official text: 24501-k10.zip in the 3GPP archive.
Same timer in EPS (TS 24.301)
TS 24.301 defines the corresponding timer for EPS. Its page quotes the EPS wording.
- T3412 (TS 24.301)
How this page was made
3GPP Scout built this page from TS 24.501 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.