Seattle-Area ZIP Codes With the Best School Scores (2026)
By Sharon Ben-Moshe · July 1, 2026
Sammamish, Mercer Island, and Bellevue ZIP codes post the highest school scores in the Seattle metro, backed by NCES proficiency data. See how six Eastside ZIPs rank and what the scores mean for families house-hunting by school quality.
Sammamish's 98074 and 98075 ZIP codes post the highest school scores in the Seattle metro area, each rating 90 and 89 out of 100 on NeighborScore, with Mercer Island's 98040 close behind at 89. According to NCES EdFacts assessment data, elementary schools in these ZIP codes post math and reading proficiency rates in the 85-91% range, well above the statewide average. This ranking covers six Eastside and King County ZIP codes with verified, non-null NeighborScore school scores, so families can compare school quality by ZIP rather than by district name alone.
How NeighborScore Ranks Seattle-Area School Quality
NeighborScore's composite index scores every US ZIP code on a 0-100 scale using overall_score = crime_score x 0.53 + school_score x 0.47 -- safety and schools only. The school_score component is built from NCES CCD enrollment data and EdFacts math and reading proficiency rates for every school inside a ZIP's boundaries, weighted toward the schools serving the most students. A ZIP's value_score (affordability relative to the Washington state median) is tracked separately and shown as context on each profile page -- it does not feed into the composite, since a $2.5 million home and a $1.3 million home can sit in ZIP codes with identical school quality.
That distinction matters on the Eastside, where school quality and affordability move in opposite directions. Mercer Island's 98040 carries a value_score of just 17 out of 100 -- far less affordable than the Washington state average of roughly 52 -- while still delivering some of the strongest classroom outcomes in King County. Buyers optimizing purely for school_score should expect to pay for it.
Seattle Metro ZIP Codes Ranked by School Score
The following six ZIP codes -- spanning Sammamish, Mercer Island, Bellevue, Redmond, and Kirkland -- carry the highest verified school_score values among Seattle-area ZIP codes in the NeighborScore database. Overall composite scores are also shown, since a high school_score does not always translate to a high overall score once crime_score is factored in.
- Sammamish 98074 -- school score 90/100, overall composite 93/100.
- Bellevue 98006 -- school score 90/100, overall composite 77/100.
- Mercer Island 98040 -- school score 89/100, overall composite 92/100.
- Sammamish 98075 -- school score 89/100, overall composite 92/100.
- Redmond 98052 -- school score 87/100, overall composite 75/100.
- Kirkland 98033 -- school score 83/100, overall composite 81/100.
NCES Proficiency Data Behind the Top Scores
The school_score gap between the top ZIP codes and the rest of the metro shows up clearly in raw NCES EdFacts numbers, not just the composite. In Sammamish's 98074, Samantha Smith Elementary posts a 91% math proficiency rate and an 89% reading proficiency rate, among the highest of any elementary school NeighborScore tracks in King County. Eastlake High School, also inside 98074, posts a 94% reading proficiency rate across its roughly 2,480 students.
Mercer Island's 98040 tells a similar story: Mercer Island High School posts a 95% reading proficiency rate and an 86% math proficiency rate, and Lakeridge Elementary posts 91% reading proficiency. GreatSchools ratings for these same schools echo the NCES figures, giving families two independent, publicly sourced data points that agree on where the strongest classroom outcomes in the metro are concentrated.
By contrast, ZIP codes closer to downtown Seattle -- like the 98103 and 98115 corridor in North Seattle -- post school scores in the 82-84 range, roughly six to eight points below the Eastside leaders, even though they benefit from a much lower cost of entry. According to NCES EdFacts data, that gap traces to school-level proficiency rates that run 5-10 percentage points behind the top Eastside elementary schools, not to enrollment size or grade span.
What the Score Gap Costs: Affordability by ZIP
None of the six top-scoring ZIP codes are cheap, but the spread among them is wide. Redmond's 98052 carries a median home price near $1.3 million as of the latest month tracked -- the most affordable of the six -- while Mercer Island's 98040 runs closer to $2.49 million. Every ZIP on this list scores well below the Washington state's average value_score of roughly 52, meaning all six are less affordable than a typical Washington ZIP; 98052 is simply less unaffordable than the rest.
Kirkland's 98033 stands out as the practical middle ground: an 83 school_score, an 81 overall composite -- the highest overall score of the six thanks to a stronger crime_score component -- and a median home price around $1.7 million, in line with Bellevue's 98006 rather than Mercer Island's premium. For families prioritizing overall livability over the single highest possible school number, that combination of scores is worth weighing before defaulting to the top of the list. NeighborScore's composite methodology applies the same crime and school weighting across every metro area it covers, so these same trade-offs show up wherever school quality and affordability pull in different directions.
Bottom Line
Sammamish's 98074 and 98075 and Mercer Island's 98040 hold the highest school scores in the Seattle metro, each in the high-80s to 90 range and backed by NCES proficiency rates well above the state average. Bellevue's 98006, Redmond's 98052, and Kirkland's 98033 round out the top six, with Kirkland offering the strongest overall composite once crime_score is factored alongside schools. Families should treat these scores as a starting point, not a final answer, and weigh each ZIP's affordability against its own budget.