| Date: | 3 November 1964 |
| Country: | Puerto Rico |
| Flag Year: | 1952 |
| Yes: | 310,431 |
| No: | 89,901 |
| Total: | 400,332 |
| Electorate: | 1,002,000 |
A referendum on eliminating special elections to fill vacant seats in the Legislative Assembly was held in Puerto Rico on 3 November 1964, alongside the general elections.[1] The reforms were approved by 77.5% of voters.[2]