A non-covered spouse can make a tax-deductible contribution up to the full year's limit as long as the couple's joint income is below $167,000 in 2010.($159,000 in 2008 and $166,000 in 2009). The deductible amount phases out to zero, though, at $177,000 ($169,000 in 2008 and at $176,000 in 2009).