The Portuguese star was drafted into the club on the heels of his sacking at Roma in 2024, and arrived in Istanbul on a wave of promise at the start of the following season.
But the mood soon soured on the Bosphorus, with the former Chelsea and Inter Milan manager sacked just six games in to the start of the 2025-26 season.
While Mourinho has since found a managerial berth at his former club Benfica in his native Portugal, according to reports the 62-year-old has left the Fenerbahce hierarchy with a punchy goodbye.
Soon after his arrival at Fenerbahce in June 2024, Mourinho was moved into the Four Seasons Hotel perched on the Bosphorus' banks, which is housed inside a former 19th century Ottoman palace.
The complex includes a spa and state-of-the-art gym, as well as indoor and outdoor swimming pools, with the former thought to be a favourite of the head coach.
Daily Mail Sport visited Mourinho at the hotel early in his tenure at the club, with staff revealing that the manager often ordered the same thing - chicken soup followed by margherita pizza, ice cream and sparkling water.
But Mourinho's arrangement was far from temporary, with the Four Seasons his only base in the city as he resisted temptation to rent a private property.
As per journalist Muge Dagıstanlı Erdogan, for Turkish outlet Yenicag, his stay came with an enormous final bill of 36.5million Turkish lira, or £656,000.
It is not clear whether the club are expected to pay for Mourinho's residence, or whether the manager himself will foot the bill.
Mourinho is thought to have been handed a jaw-dropping £7.7m payout to leave Fenerbahce earlier this season.
But should Mourinho not find himself settling his tab in Istanbul, the situation might have a parallel with a period earlier in his career, during his time at Manchester United.
Mourinho - who is based in London and his native Portugal - opted not to put down roots in the North between 2016 and 2018, and instead stayed at The Lowry Hotel for 895 days.
The then-Red Devils manager accrued a bill of £537,000 for the duration of his stay.
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