Regular rate is deceptively simple and quietly decisive. Get it wrong and every downstream overtime and premium calculation inherits the error — often by a lot.
Start with what counts as compensation
Non-discretionary bonuses, shift differentials, and certain incentives belong in the regular rate. Leaving them out understates exposure; including the wrong things overstates it. The record has to drive the answer.
Let the record settle the argument
The most defensible regular-rate figure is the one you can reconstruct from the payroll data itself, period by period, without hand-waving. That is the standard worth holding your own analysis to.