Tennessee area codes — detailed data

NANPA NPA database, current as of July 28, 2026.

Full numbering detail for every active Tennessee area code: lineage (which code it split from), NANPA exhaust projections, dialing plans and jeopardy status. This is the working data behind the overview page.

Aggregate footprint: the state's 8 geographic codes currently carry 3,760 active NXX prefixes over 385 rate-center anchorings, with 2,650 prefixes in thousands-block pooling. 6 of the codes serve territory inside FCC top-100 metropolitan statistical areas.

Lineage: 423 came out of 615 in 1995; 629 came out of 615 in 2015; 729 came out of 423 in 2025; 731 came out of 901 in 2001; 865 came out of 423 in 1999; 931 came out of 615 in 1997. The remaining codes (615, 901) date back to the plan's early assignments.

Dialing plans: 6 codes use plain ten-digit local dialing (10D); 2 still allow seven-digit local calls. Overlay territories always dial ten digits; the 2021 988-hotline transition moved most others to ten digits as well.

The tightest capacity in the state is 901, projected to exhaust 2Q 2042.

Status: no Tennessee code is currently in jeopardy or active relief planning — capacity is adequate near-term per NANPA.

Code-by-code notes

615 — spawned 423, 931, 629; overlaid by 629; exhaust forecast 3Q 2057.

423 — spawned 865, 729; carved from 615; overlaid by 729; exhaust forecast 1Q 2081; spans two time zones.

901 — spawned 731; exhaust forecast 2Q 2042.

931 — carved from 615; exhaust forecast 2Q 2051; spans two time zones.

865 — carved from 423; exhaust forecast 4Q 2046.

731 — carved from 901; exhaust forecast 2Q 2097.

629 — carved from 615; overlaid by 615; exhaust forecast 3Q 2057.

729 — carved from 423; overlaid by 423; exhaust forecast 1Q 2081; spans two time zones.

Time-zone note: 423, 729, 931 span two time zones — rare among NANP codes.