WASHINGTON – Millions of families and businesses will get hit by big tax increases a lot sooner than many realize if Congress and the White House don’t agree on a plan to skirt the year-end fiscal cliff of higher tax rates and big government spending cuts.

In fact, they already have.

More than 70 tax breaks enjoyed by individuals and businesses expired at the end of 2011. If Congress doesn’t extend them retroactively back to the beginning of this year, a typical middle-class family could face a $4,000 tax increase when it files its 2012 return in the spring, according to an analysis by H&R Block, the tax preparing giant.