work overtime
do overtime
work extra hours
take on extra hours

She's not going to get any less dead, just because you work more bloody overtime!

The money earned by working overtime was spent in books.

"We have no trouble getting people to work overtime or on Sundays."

A central London dentist working serious overtime in the small hours of the morning.

Her husband now works overtime and delivers papers for just one route.

The team had only six months, so the craftsmen worked triple overtime.

For many employees, the commitment to work overtime is made at the eleventh hour.

But bosses who have to ask their employees to work overtime are caught in a bind, too.

Motivation and sales dropped, and the company lost much of its ability to get employees to work free overtime.

If you expect employees to work regular overtime, it's a good idea to state this clearly in the employee's contract, together with: