How scoring works
Maricopa County's letter grades are voluntary — most establishments don't participate. But every inspection records violations in three classes defined by the FDA Food Code. We turn those into two transparent, reproducible signals.
Violation classes
- Priority — directly increases the risk of foodborne illness (e.g. employees not washing hands when required).
- Priority foundation — conditions that lead to priority violations (e.g. no soap at the hand-wash sink).
- Core — general maintenance and sanitation (e.g. a missing hand-washing reminder sign).
Some mobile-food violations cite the Maricopa County Environmental Health Code (MCEHC) instead of the FDA Food Code; these appear as “County code” violations.
Equivalent grades (°)
When an establishment's most recentinspection carries a county grade, we show it. When it doesn't — most establishments don't participate, and some stop participating — we apply the county's own published grading matrix to that latest inspection's violation counts and show the result marked with ° — for example B°. We never carry an old county grade forward past newer inspections: the badge always reflects the latest visit. Same rules, same thresholds, applied consistently to everyone:
| Grade | Priority | Priority foundation |
|---|---|---|
| A | 0 | 0 |
| B | 0 / 1 | 1–4 / 0–2 |
| C | 0 / 1 / 2 | 5 / 3–4 / 0–2 |
| D | Anything worse — or legal action for a pattern of non-compliance | |
The health score (0–100)
Each routine inspection and re-inspection gets a score:
100 − 15 × priority − 5 × foundation − core (max 10)
An establishment's overall score is the time-weighted average of its inspection scores over the county's rolling 3-year window, with a one-year half-life — so recent inspections matter roughly twice as much as those a year old. Advisory and review visits are shown in the history but never affect the score.
Hard floor:an establishment with an immediate suspension or a D-equivalent inspection in the last 6 months is capped in the “Poor” band regardless of its average — recent serious problems shouldn't be papered over by an otherwise good record.
Data source & freshness
All data comes from Maricopa County Environmental Services public records, which cover a rolling 3-year window. The county posts results after an internal review of about three days; we refresh restaurant records at least weekly. Every establishment page links to its official county record.
PlateScore is independent and not affiliated with Maricopa County. Scores are computed estimates intended to make public data easier to understand — not an official rating.