Prefix 317-551 — Indianapolis, IN

NANPA CO code assignment, current as of July 28, 2026.

Area code
317
Prefix (NXX)
551
Rate center
Indianapolis
State
Indiana
Time zone
Eastern
Code holder
OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC
OCN
2964
Pooled
Yes (thousands-block pooling)
Assigned
2012-01-09
LATA
336

317-551 identifies a block of numbers in Indianapolis, IN, within the 317 area code. Every US prefix is tied to exactly one rate center; this one is Indianapolis.

The rate center lies in the Indianapolis-Carmel-Greenwood, IN Metropolitan Statistical Area. The serving LATA is 336. Local time follows the Eastern zone.

Treat the on-screen number as a hint, not evidence — 317-551 can be spoofed like any US prefix. If a call feels off, verify through an official callback number and file a complaint with the FCC or FTC.

NANPA's central-office code records list OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC (OCN 2964) as the code holder, assigned January 9, 2012. Because 317-551 participates in thousands-block pooling, individual 1,000-number blocks may belong to other carriers than the code holder.

Neighboring prefixes

Prefixes adjacent to 317-551
PrefixRate centerCode holder
317-548 West Newton PAETEC ITEL, LLC
317-549 Indianapolis INDIANA BELL TEL CO INC
317-550 Indianapolis BANDWIDTH.COM CLEC, LLC - IN
317-552 Indianapolis BANDWIDTH.COM CLEC, LLC - IN
317-553 Indianapolis AMERICAN MESSAGING SERVICES, LLC
317-554 Indianapolis TELEPORT COMMUNICATIONS AMERICA, LLC - IN

FAQ

Where is 317-551 located?

The prefix is assigned to the Indianapolis rate center in IN, area code 317. It is part of the Indianapolis-Carmel-Greenwood, IN Metropolitan Statistical Area.

Which company owns 317-551 numbers?

OMNIPOINT COMMUNICATIONS MIDWEST OPERATIONS, LLC holds the code, but the prefix is pooled — individual thousands-blocks can be assigned to other carriers, and numbers may be ported to any provider.

Is a call from 317-551 safe to answer?

The prefix itself says nothing about the caller. Legitimate Indianapolis businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.