| City: | Palmer, Puerto Rico |
| City Alias: | Rio Grande |
| County: | Rio Grande County |
| Timezone: | Atlantic (GMT -04:00) |
| Local Time: | 8:42:12 PM |
| Population: | No Population Data |
| Area Codes: | 787 / 939 |
| Classification: | PO Box |
| Coordinates: | 18.3711, -65.7747 |
| Quick Link: |
Palmer is a small community in Rio Grande municipality, Puerto Rico, served by a branch post office that maintains 549 PO Boxes. The community occupies just 0.13 square miles, making it one of the smallest PO Box ZIP territories in Puerto Rico. While classified as PO Box only, the post office does handle limited street delivery along Calle Principal, the single street with 57 delivery points.
The Palmer post office operates as a branch of the Rio Grande main facility. Mail addressed to either Palmer or Rio Grande is accepted, though Palmer is the preferred city name for this ZIP. Both city and rural carrier routes serve the area, creating a mixed delivery pattern typical of Puerto Rico's compact communities where urban density meets rural character.
With 549 residential delivery points and 31 business locations, Palmer functions as a small commercial and residential node within the larger Rio Grande area. The post office provides essential mail access for this eastern Puerto Rico community, where PO Boxes remain the primary delivery method despite the availability of some street delivery service.
Mail can be addressed to Palmer, PR 00721 or Rio Grande, PR 00721. For PO Box delivery:
[Recipient Name]
PO Box [Number]
Palmer, PR 00721Limited street delivery is available on Calle Principal with unit designators.
Only one street in delivery area: Calle Principal (Main Street) with multi-unit delivery points.
ZIP Code 00721 is designated for PO Box delivery only; business establishment and employment data are not available.
| # Residential Mailboxes: | 0Source: USPS |
| # Business Mailboxes: | 0Source: USPS |
| Total Delivery Receptacles: | 961Source: USPS |
| Single Family Delivery Units: | 0Source: USPS |
| Multi Family Delivery Units: | 0Source: USPS |
| # of Businesses: | 0Source: CBP |
| 1st Quarter Payroll: | $0Source: CBP |
| Annual Payroll: | $0Source: CBP |
| # of Employees: | 0Source: CBP |
ZIP Code 00721 is located in Rio Grande County, Puerto Rico, within the San Juan-Bayamon-Caguas, PR Metropolitan Statistical Area (CBSA 41980). This Metro area has a population of 2,478,905 people, about 0.00% of whom live in ZIP Code 00721. It covers 0 sq mi of land and a water area of 0 sq mi.
| CBSA Name: | San Juan-Bayamon-Caguas, PRSource: Census |
| CBSA Number: | 41980Source: Census |
| CBSA Type: | MetroSource: Census |
| CBSA Division: | --Source: Census |
| CBSA Population: | 2,478,905Source: Census |
| MSA: | San Juan-Caguas-Arecibo, PR CMSASource: Census |
| Land Area: | --Source: Census |
| Water Area: | --Source: Census |
| Congressional District: | No DistrictsSource: USPS |
| Congressional Land Area: | sq miSource: Census |
| PMSA: | San Juan-Bayamon, PR PMSASource: Census |
| Intro Date: | < 2004-10Source: ZIP-Codes.com |
| Place FIPS Code: | 7258666Source: Census |
| Place Name: | Palmer comunidad; Puerto RicoSource: Census |
We could not locate which school district 00721 belongs to, but we will update this once new district data is released. There are no public schools nor private schools with a mailing address in this ZIP Code. Listing Nearby schools instead. It also has 6 colleges, universities or post secondary education institutions nearby which would be a short commute to.
Our sources include trusted federal and licensed data from the United States Postal Service, U.S. Census Bureau, U.S. Geological Survey, Centers for Medicare & Medicaid Services, and the National Center for Education Statistics, along with proprietary datasets created by ZIP-Codes.com. Data last updated on February 1, 2026.