Portuguese legislative election, 1991 Opinion Polling 116 seats needed for a majority

| Date_Released | Polling_institute | Social_Democratic | Socialist | Green_Communist | Democratic_and_Social_Centre | Lead_ |
|---|---|---|---|---|---|---|
| October 6, 1991 | Election Results | 50.6% 135 seats | 29.1% 72 seats | 8.8% 17 seats | 4.4% 5 seats | 21.5% |
| October 6, 1991 | Exit Poll - RTP1 Universidade Católica | 48.0% – 51.9% | 28.5% – 31.5% | 7.5% – 10.0% | 4.5% – 5.5% | 19.5% – 20.4% |
| October 6, 1991 | Exit Poll - TSF/Expresso Euroexpansão | 45.8% – 50.2% | 29.8% – 33.9% | 6.8% – 9.1% | 3.7% – 5.5% | 16.0% – 16.3% |
| October 6, 1991 | Exit Poll - Antena1 Euroteste | 47.0% – 50.0% | 31.0% – 34.0% | 7.5% – 10.0% | 4.0% – 5.0% | 16.0% |
| September 28, 1991 | Euroteste | 47.3% | 35.5% | 8.5% | 4.1% | 11.8% |