Even before the current economic downturn, rates of employer-sponsored insurance (ESI) declined substantially, falling six percentage points between 2000 and 2008 for nonelderly Americans. During a previously documented decline in ESI, from 1987 to 1996, the fall was found to be the result of a reduction in enrollment or ‘take-up’ of offered coverage and not a decline in employer offer/eligibility rates. In this paper, we investigate the components of the more recent decline in ESI coverage by firm size, using data from the MEPS-IC, a large nationally representative survey of employers. We examine changes in offer rates, eligibility rates and take-up rates for coverage, and include a new dimension, the availability of and enrollment in dependent coverage. We investigate how these components changed for employers of different sizes and find that declining coverage rates for small firms were due to declines in both offer and take-up rates while declining rates for large firms were due to declining enrollment in offered coverage. We also find a decrease in the availability of dependent coverage at small employers and a shift towards single coverage across employers of all sizes. Understanding the components of the decline in coverage for small and large firms is important for establishing the baseline for observing the effects of the current economic downturn and the implementation of health insurance reform.