How Many Votes Does a Party Need to Win a Seat in the Israeli Knesset?

After voting concludes in Israeli elections, the process of determining each list's share of the 120 parliamentary seats begins, according to legal rules that define who gets the seats and how undetermined seats from the first stage are distributed.

According to a report published by i24news, this mechanism raises questions about the number of votes required to win a single seat, the fate of votes insufficient for an additional seat, and the role played by surplus vote agreements in altering the final distribution.

How many votes equal one seat?
The calculation process begins by dividing the total valid votes received by lists that exceeded the electoral threshold by the Knesset's 120 seats. The result is known as the "general divisor," which is the base number of votes necessary for a seat during the initial distribution phase.

The number of votes corresponding to a seat is influenced by several factors, most notably voter turnout, the number of valid votes, and the volume of votes obtained by lists that surpass the electoral threshold.

Therefore, knowing the number of eligible voters is not enough to determine the votes needed to win a seat; instead, one must calculate the valid votes received by qualified lists participating in seat distribution.

What is the role of the electoral threshold?
Each electoral list must receive at least 3.25% of the valid votes to enter the Knesset seat distribution.

Votes received by lists that do not reach this percentage are excluded from the distribution of the 120 seats.

The more votes granted to lists that failed to cross the electoral threshold, the lower the total pool of votes used for distributing seats among qualified lists.

What happens to remaining votes?
If a list receives 55,000 votes and the general divisor is 37,500 votes, it obtains one seat in the initial calculation, leaving a surplus of 17,500 votes.

These votes are not simply discarded, as some seats may remain undistributed after the initial phase, and they are allocated according to the Bader-Ofer method, which considers the number of remaining votes for each list relative to the number of seats already won.

How do surplus vote agreements affect outcomes?
Surplus vote agreements allow two electoral lists to agree, before voting, to combine their remaining votes when distributing seats not decided in the initial phase.

In this stage, the two lists are calculated according to the rules associated with the agreement, then it is determined which one receives the additional seat. This mechanism can grant a party an extra seat even if it did not have the largest surplus of votes when viewed individually.

Consequently, surplus vote agreements can influence the final distribution of seats, especially when competition between lists is close.

Does the number of Knesset seats change from election to election?
The Israeli Knesset consists of 120 seats, and this number does not change from one election to another. However, the number of votes represented by a seat varies depending on the total valid votes received by lists exceeding the electoral threshold.

If the total of these votes reaches 4.5 million, the general divisor is 37,500 votes per seat. If it reaches four million, it drops to approximately 33,333 votes, while rising to about 41,667 votes if the total reaches five million.

These figures remain illustrative for the initial calculation, as the final distribution of seats is only determined after voting ends, votes are counted, and rules for distributing remaining seats are applied.

Thus, the number of votes needed to win a seat in the Knesset is not defined by a fixed figure but depends on the tally of valid votes, the electoral threshold, the method of distributing remaining seats, and the impact of surplus vote agreements.