Most of the world's population occurs in southern Britain and Brittany, but it is found in scattered locations around the coast of Europe as far as Corsica and Italy, and south to the Canary Isles.

Sea stork's-bill is a perennial monoecious herb which typically grows in rosettes pressed flat to the ground, with a deep tap root that allows it to survive through the summer on dry soils.

For technical confirmation, the pit at the apex of the mericarp is hidden by long hairs in sea stork's-bill, whereas it is generally visible in the other species.

[9] A 2012 study of the genetics of sea stork's-bill found that populations on the Atlantic coast of Europe lacked diversity, and plants throughout this area were all closely related to each other, as if long-distance dispersal events were frequent.

The low levels of diversity might be due to founder effects, whereby a small number of individuals have given rise to the entire Atlantic seaboard population.

[10] Sea stork's-bill is almost entirely restricted to western Europe, where it has a very Atlantic distribution, mainly in south-western Britain,[11] southern Ireland and Brittany.

[21][22] An exception is the Long Mynd in Shropshire, where it was found over 200 years ago by the Jamaican-English botanist Mary McGhie and is still present, in U1 sheep's sorrel grassland on a south-facing shale hillside, at an altitude of 220 m above sea level.

[23][24][25] Secondary populations occasionally appear on roadsides, railway lines, walls, in quarries and car parks, but these tend not to persist.

Its Ellenberg values in Britain are L = 9, F = 4, R = 6, N = 6, and S = 3, which supports the conclusion that it favours brightly lit places with low moisture, circumneutral acidity, moderate fertility, and high salinity.

[29] While it is potentially a perennial, sea stork's-bill often behaves as a spring annual, becoming abundant in a wet year and sometimes disappearing above ground in a dry summer.