There are 129 seats in the Scottish Parliament at Holyrood. The most recent election to the Scottish Parliament took place on the 6th of May 2021. Following the election, the SNP initially formed a continuing minority government, before entering into cooperation talks with the Greens. That led to the formation of a cooperation agreement between the two parties, with the Greens entering Government with two ministers.
However, unlike a full coalition government, the Greens are not represented in cabinet. Additionally, the two parties have identified areas of disagreement where they may vote separately, and have further stated the deal does not preclude each working with other parties where they consider it appropriate.
The Presiding Officer Alison Johnstone (shown in black) was elected as a Green MSP. By convention, the PO gives up their party status to impartially chair the Scottish Parliament. As such, the PO does not normally cast a vote. They will however do so if parliament is equally split on a given issue.
This follows a long-standing convention of parliamentary chairing in the UK, whereby the chair will vote for more debate where possible, and the status quo otherwise. In practice this means that in the case of a tie, legislation in its early stages will be passed onto later stages, whereas final stage legislation, other motions, and amendments will fall.
The following chart shows the seats won at each Holyrood election – it does not account for any changes that took place in the middle of a term. Parties are displayed in their current vote share order. Note that in 2005, Scotland dropped from 72 to 59 seats at Westminster.
Elections to the Scottish Parliament use the partly-proportional Additional Member System (AMS). This combines the familiar First Past the Post (FPTP) system with a proportional List system. The 73 constituencies each elect a single MSP via FPTP. Constituencies are grouped into a total of 8 regions, each of which elects a further 7 MSPs from a proportional list. These list MSPs are allocated taking into account the constituency seats, meaning parties with many constituencies will win few, if any, list seats.