Sometimes I’d work less than 40 hours but some of that would still be off-the-clock work. Can I claim that as well?

Yes. It’s not unpaid overtime pay, but as part of an overtime lawsuit, the O’Brien Law Firm also often makes additional claims for unpaid wages that aren’t otherwise covered under the overtime laws. However, in Texas, those unpaid wages that aren’t unpaid overtime aren’t subject to potential doubling by the court. But it’s still your money that belongs in your pocket – not your employer’s pocket.