#1 Carmella - 287 days (WWE Money in the Bank 2017)

Former WWE SmackDown Women's Champion Carmella has the distinction of being the WWE Superstar to hold the Money in the Bank contract for the longest time before cashing in.
Carmella won the first-ever Women's Money in the Bank ladder match in 2017 at the Money in the Bank pay-per-view event. After interference from James Ellsworth, Carmella defeated Becky Lynch, Natalya, Tamina, and Charlotte Flair to become Miss Money in the Bank.
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However, two days later, SmackDown General Manager Daniel Bryan changed things. Bryan stated that due to Ellsworth's interference, Carmella would be stripped of the Money in the Bank contract.
A re-match was held on that edition of SmackDown LIVE in which Carmella once again successfully captured the Money in the Bank briefcase.
Carmella waited an agonizing 287 days before successfully cashing in her Money in the Bank contract. Then-SmackDown Women's Champion Charlotte Flair was viciously attacked by the debuting Billie Kay and Peyton Royce on the post-WrestleMania 34 edition of SmackDown LIVE.
This assault by The IIconics provided Carmella with the perfect opportunity to cash in her Money in the Bank contract on Charlotte Flair and capture the SmackDown Women's Championship for the first time in her career.