Let’s say a disabled beneficiary goes back to work part-time, and earns $13 an hour for 15 hours a week. His total monthly earnings would be $845. Because that amount falls below $1,000, he would be able to keep a total of $1,845 a month. But if he upped his hours to 20 hours a week, he would then be earning $1,127 a month, which would put him over the threshold for collecting benefits. After the nine-month trial period, he would be stripped of benefits and thus would have only $1,127 in earnings. So by working five more hours a week, he loses $718 a month.
More on the “cash cliff” in disability benefits.