ZIP Code 00721 is located in Palmer Puerto Rico. Portions of 00721 are also in Mameyes II and Mameyes I. 00721 is primarily within Rio Grande Municipio, with some portions in Luquillo Municipio.
| ZIP Code Name | Palmer |
| Primary County | Rio Grande Municipio |
| ZIP Code Type | PO Box |
| Area Code(s) | 787 / 939 |
| Current Time | AST |
| Coordinates | 18.37735176,-65.85108185 |
| Adjacent ZIP Codes | |
| Cities/Towns in 00721 | |
| Metropolitan/Micropolitan Stat Area | San Juan-Bayamón-Caguas, PR |
| Time Zone | Atlantic Standard Time |
| IANA Timezone | America/Puerto_Rico |
| Area | 2 Square Miles |
| School Districts in 00721 |