| Election Name: | 1994 Selwyn by-election |
| Country: | New Zealand |
| Flag Year: | 1994 |
| Type: | parliamentary |
| Ongoing: | no |
| Previous Election: | 1993 New Zealand general election |
| Previous Year: | 1993 general |
| Next Election: | 1996 New Zealand general election |
| Next Year: | 1996 general |
| Turnout: | 21,052 |
| Candidate1: | David Carter |
| Party1: | New Zealand National Party |
| Popular Vote1: | 8,906 |
| Percentage1: | 42.32% |
| Candidate2: | John Wright |
| Party2: | Alliance (New Zealand political party) |
| Popular Vote2: | 8,488 |
| Percentage2: | 40.34% |
| Candidate4: | Marian Hobbs |
| Party4: | New Zealand Labour Party |
| Popular Vote4: | 2,173 |
| Percentage4: | 10.33% |
| Candidate5: | Tim Shadbolt |
| Party5: | New Zealand First |
| Popular Vote5: | 1,165 |
| Percentage5: | 5.54% |
| Member | |
| Before Election: | Ruth Richardson |
| After Election: | David Carter |
| Before Party: | New Zealand National Party |
| After Party: | New Zealand National Party |
The Selwyn by-election, a by-election in the New Zealand electorate of Selwyn – a predominantly rural district in the Canterbury Plains in New Zealand's South Island – took place on 13 August 1994. The previous sitting MP, Ruth Richardson, precipitated the poll by resigning from parliament. Richardson planned to retire from politics, having been removed as Minister of Finance the previous year.
The by-election was significant, as National held on to the majority of the House of Representatives by only one seat (50 to 49). This meant the party would have lost its majority in the House if it failed to retain the seat, and it would have required the formation of a coalition or a confidence-and-supply agreement with another parliamentary party – probably New Zealand First or the Alliance – to maintain governance.
All "major" New Zealand political parties of the day contested the by-election. David Carter, the National Party candidate, won the seat, and therefore the distribution of seats in Parliament did not change . In second place, and only around four hundred votes behind Carter, came the Alliance's John Wright, in a result that surprised many commentators. National's traditional opponent, the Labour Party, placed a distant third. The fourth "major" candidate represented the New Zealand First party: Tim Shadbolt, then Mayor of Invercargill.[1]
The following table shows the official results as published by the Electoral Commission.