Keep one argument pattern in mind

SUMIFS can handle a single criterion as well as several, so it can provide a consistent structure for conditional totals that may become more detailed later. The source emphasizes a practical difference from SUMIF: SUMIFS begins with the values to add, followed by range-and-criterion pairs. SUMIF instead begins with the range to test. Confusing those orders is an avoidable source of incorrect formulas.

Expand only when the reporting question changes

Starting with one criterion in SUMIFS can make later additions more straightforward, because the sum range remains in the same position. That does not mean every calculation requires extra conditions. Add each pair to represent a real requirement and ensure its range corresponds to the records being totaled. The goal is maintainable logic: someone reading the formula should be able to identify the values being summed and the conditions that make them qualify.

Use SUMIFS for a Total That May Gain More Requirements