Sam Younger, chief executive of the Charity Commission, will leave his post next year.
The regulator has begun advertising for a replacement for Younger, who joined the commission in September 2010.
A spokeswoman for the commission said that Younger had decided to stand down to give his successor adequate time to bed into the role before the general election in 2015.
"His initial contract was due to come to an end in August 2013 and at that time Sam made it clear that he did not wish to do a full second three-year term," she said.
"He thought it best to hand over to a successor so he or she could get their feet fully under the table well before a May 2015 general election and subsequent funding negotiation.
"Sam’s contract was therefore extended for one year to August 2014."
She said Younger had not decided what he wanted to do when he left the commission but he was "unlikely to seek another full-time role".
Younger’s successor is likely to be paid slightly less than he has been receiving: he was paid about £130,000 in 2012/13, but the regulator is advertising the role on a salary of "up to £125,000, plus a range of benefits".