A huge difference is that Incapacity Benefit is not means tested - everyone who has paid sufficient National Insurance contributions is entitled to it, provided they meet the ill-health criteria.
Income support is means tested - too much money in the bank, or too much income, and you can't get it.
Sorry to correct you Ethel, but Incapacity Benefit can be paid after three days' incapacity.
Incapacity Benefit (IB) is a National Insurance (NI) Contribution based benefit whilst Income Support (IS) isn't and IS is called a means tested benefit whilst IB is a non-means tested benefit.
If a benefit is means teated, it is dependant upon yir income (which includes savings, shares, Premium Bonds etc) being below a level set by Parliament.
Nae bother, I work for Jobcentre Plus and used to work on the Incapacity Benefit section as one of the Raters (the ones who award benefit) and as a Supervisor. If you are employed, IB is normally paid following 28 weeks' SSP but it can be paid earlier if the SSP ends for various reasons.
Self-employed folk don't qualify for SSP because they are not classed as employed earners so they can get the IB after three days (or two as said earlier.)
There's a lot of mis-conceptions about the various benefits and I'd hate for someone to miss out because of wrong info they've read here.