Prefix 787-400 — Guaynabo, PR
787-400 identifies a block of numbers in Guaynabo, PR, within the 787 area code. Every US prefix is tied to exactly one rate center; this one is Guaynabo.
The rate center lies in the San Juan-Bayamón-Caguas, PR Metropolitan Statistical Area. The serving LATA is 820. Local time follows the Atlantic zone.
Treat the on-screen number as a hint, not evidence — 787-400 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 LIBERTY MOBILE PUERTO RICO INC. (OCN 639J) as the code holder, assigned September 26, 2005. Because 787-400 participates in thousands-block pooling, individual 1,000-number blocks may belong to other carriers than the code holder.
Neighboring prefixes
| Prefix | Rate center | Code holder |
|---|---|---|
| 787-397 | Rio Piedras | LIBERTY MOBILE PUERTO RICO INC. |
| 787-398 | Rio Piedras | LIBERTY MOBILE PUERTO RICO INC. |
| 787-399 | Rio Piedras | LIBERTY MOBILE PUERTO RICO INC. |
| 787-401 | Rio Piedras | LIBERTY MOBILE PUERTO RICO INC. |
| 787-402 | Rio Piedras | LIBERTY MOBILE PUERTO RICO INC. |
| 787-403 | Rio Piedras | LIBERTY MOBILE PUERTO RICO INC. |
FAQ
Where is 787-400 located?
The prefix is assigned to the Guaynabo rate center in PR, area code 787. It is part of the San Juan-Bayamón-Caguas, PR Metropolitan Statistical Area.
Which company owns 787-400 numbers?
LIBERTY MOBILE PUERTO RICO INC. 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 787-400 safe to answer?
The prefix itself says nothing about the caller. Legitimate Guaynabo businesses and spoofed robocalls can both display it. Never share personal data with an unverified inbound caller.