Baby names starting with B: girls and boys

The most used girls' names beginning with B in 2025

B is a small letter and an unusually informal one. The ONS counted 5,726 girls given a B name in 2025 across 217 different spellings, a little over 2 per cent of all girls named. What stands out is how many of the leaders are pet forms used as full names in their own right: Bonnie, Billie, Betsy, Betty and Bobbie are all short forms that no longer need a long version behind them.

The most used boys' names beginning with B in 2025

The boys' letter is slightly larger at 8,111 babies across 241 names, and it splits cleanly in two. Benjamin is the one long formal name near the top; everything else in the leading group is a nickname or a surname. Bobby, Billy, Barney and Bertie come from the first tradition, Brody, Blake, Brodie and Bailey from the second.

Which B names are rising and which are falling

Climbing

There is very little upward movement to report, because the ONS only publishes rank changes for names inside the top 100 and B has just two on each side. Neither rose in 2025. The honest positive story for the letter is the ten-year column for Bonnie, which is up 75 places since 2015 and was a new entry to the top 100 in that comparison, showing how recent the name's revival is.

Slipping

Both girls' entries fell, and one fell hard. Bonnie dropped 32 places in a single year, from 16th to 48th, which is the largest single-year fall of any name in the entire 2025 girls' top 100. Bella lost 15 places and is down 30 since 2015. Among boys, Benjamin held its rank exactly and Bobby lost 12.

What the published change columns cannot tell you

Beatrice, Billie, Betsy, Brody, Beau, Billy, Bodhi and every other B name below rank 100 has an exact 2025 count in the ONS full list but no published change figure. Their positions here are real; any claim about whether they are rising would not be, so none is made. The ONS full dataset also redacts names given to two or fewer babies, which removes a long tail of one-off B spellings entirely.

How big a letter B really is

B is one of the quieter letters of the alphabet on both sides, fifteenth for girls and fifteenth for boys by number of babies. It is also one of the least top-heavy: Bonnie takes 15 per cent of the girls' letter and Benjamin 10 per cent of the boys'. That means a B name is a genuinely uncommon choice without being an odd one, which is a combination most letters do not offer.

The letter's second feature is the flower-and-object group that sits just below the leaders. Blossom, at 124 babies, is the clearest example of the nature naming that dominates other parts of the ONS list arriving late in B. Beatrice and Beatrix, meanwhile, are counted as two separate names by the ONS, with 401 and 173 babies; together they would rank considerably higher than either does alone.

Further B names in the published 2025 list

The ONS full list does not stop at the tables above, and the counts stay exact all the way down. For girls the next names in order of use are Brielle at 76, Bronte at 76, Brianna at 75, Bianca at 73, Barkat at 72, Blair at 72, Bethany at 67, Blake at 65, Birdie at 64, Baani at 63, Bobbi at 57, Bailey at 52. For boys they are Bowen at 129, Bradley at 119, Bear at 117, Beauden at 110, Bowie at 109, Bilal at 99, Bodie at 89, Ben at 79, Bryan at 77, Bjorn at 70, Benny at 69, Brian at 68. Each figure is the exact number of babies registered with that exact spelling during 2025, taken from the ONS full-list table rather than from the top 100. The letter carries 217 different girls' names and 241 different boys' names in the published data altogether, and any name given to two or fewer babies has been removed from it.

Choosing a B name: what the data changes

Because so many B names are short forms, think about what happens on a formal document. Betsy and Betty are complete legal names in these figures, not abbreviations of Elizabeth, and Elizabeth itself is recorded separately with its own count. The same is true of Bobby and Robert, and Billy and William. The ONS records exactly what was written on the certificate, which is worth remembering when you decide which version to register.