on a first-name basis

Idioms  

1. Quite familiar and friendly, as in Practically all the guests were on a first-name basis. This idiom alludes to the fact that using a person's given name betokens familiarity. [Second half of 1900s]

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Example Sentences

He was quickly on a first-name basis with Paul Rudolph, the intimidating head of the school, and the influential art historian Vincent Scully.

From The Wall Street Journal • Nov. 28, 2025

Many of the players are on a first-name basis with the city, and if they aren’t, they’re identified by a nickname.

From Los Angeles Times • Nov. 4, 2025

Murray hated flying and he hated New York, yet every big-name mixologist in the East Village seemed to know him on a first-name basis.

From Seattle Times • Nov. 9, 2023

Locals are on a first-name basis with significant nearby fires, and they become familiar conversational touchstones.

From Slate • Sep. 18, 2023

“We’re on a first-name basis, so why does it even matter?”

From "Dry" by Neal Shusterman and Jarrod Shusterman