This is a list of transfers involving clubs that played in the 2020 League of Ireland Premier Division and 2020 League of Ireland First Division.
The pre-season transfer window opened on 1 December 2019 and closed on 22 February 2020 for domestic transfers and on 2 March 2020 for foreign transfers.
Players without a club may join one at any time, either during or in between transfer windows.
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