| Cover | Nov. 08, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Nov. 8, 2021 |
| Entity Registrant Name | POSTAL REALTY TRUST, INC. |
| Entity Incorporation, State or Country Code | MD |
| Entity File Number | 001-38903 |
| Entity Tax Identification Number | 83-2586114 |
| Entity Address, Address Line One | 75 Columbia Avenue |
| Entity Address, City or Town | Cedarhurst |
| Entity Address, State or Province | NY |
| Entity Address, Postal Zip Code | 11516 |
| City Area Code | 516 |
| Local Phone Number | 295-7820 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Title of 12(b) Security | Class A Common Stock, par value $0.01 per share |
| Trading Symbol | PSTL |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | true |
| Entity Ex Transition Period | false |
| Entity Central Index Key | 0001759774 |
| Amendment Flag | false |
