Seattle Pizza Index (SPI) tracks the price of pizza in Seattle over time.
It started with an $8 slice. During her 2025 mayoral campaign, Katie Wilson walked through Capitol Hill holding a slice from Big Mario’s and made the case that Seattle’s housing crisis was driving up the cost of everything — including pizza. The video went viral. She won.
Now she’s mayor. And we’re watching the pizza.
SPI is a data-driven project with a simple premise: if the cost of living in Seattle is really driven by policy, we should be able to see it in something as basic as a slice of pizza. Every quarter, we collect prices from 20 Seattle pizzerias and publish the results — no spin, no commentary, just numbers.
The index does not advocate for or against specific policies or candidates. It records publicly available menu prices using a documented methodology and publishes those results so anyone can see how prices are moving over time.
Draw your own conclusions.