How much more do I take home outside IR35 at £300/day?
At £300/day over 220 billable days (£66,000 contract revenue), outside IR35 nets you £48,445 per year through a limited company, versus £43,555 per year inside IR35 via an umbrella. That is a difference of £4,890 per year (11.2% more), before accounting for accountancy fees you'd pay either way.