Lily Bottomley, the pub's events and social media manager, said the buzz started online last week before the double album was released on Friday, with The Black Dog confirmed as the 17th track.
She had to call in staff to cope with demand, and the pub in the city's Vauxhall district has capitalised on its new-found fame with a "Swift" burger and "(Taylor's Version)" cocktails.
Taylor Swift's latest album broke Spotify records for most-streamed album in a single day this year. (AP PHOTO)
Bottomley could not be absolutely certain her Black Dog was the same one mentioned, but she said there had previously been a "certain blonde regular" at the pub.
Swift describes her 11th studio album on Instagram as: "An anthology of new works that reflect events, opinions and sentiments from a fleeting and fatalistic moment in time".
Fans largely believe it is about her former British boyfriend Joe Alwyn. Swift has referenced other London locations in her songs that sparked interest in where the couple had spent time in the British capital.
They split in April 2023 after six years of dating.
"We're a very cosy small neighbourhood pub, so something like this happening is a dream," Bottomley said.
"We're just so thankful to the fans because they've just been amazing."
Katie, a web developer and "Swifty" visiting from Northern Ireland for her birthday, said she liked going to places mentioned in songs.
"I was in New York last year, and I also did a little Taylor Swift walking tour by myself of the places that she's mentioned there."
Emilia, a masters student from Vienna, said she could picture Swift going to the pub. "I appreciate her because she's lyrically a genius," she said.
Spotify said on Friday that "Poets" broke the record for the platform's most-streamed album in a single day this year, achieving the feat in less than 12 hours.
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