(in the US) FDIC insurance treats business accounts the same as personal accounts. Bank accounts for corporations, partnerships, and unincorporated associations get the full $250k in FDIC coverage, separate from any owner or member of the organization.

(in the EU) the sum is $100,000 and also applies to companies.

FDIC insurance covers business accounts up to $250k per institution. The FSCS scheme in the UK covers business accounts up to £85k per institution. Where are you getting this idea from?

This is not true for FDIC.