ZIP 98040 vs ZIP 98118

This side-by-side compares ZIP 98040 (Mercer Island, WA) and ZIP 98118 (Seattle, WA) using the same Census ACS 5-Year table fields for both — no averages swapped in, no national proxies. ZIP 98040 has a population of 22,699 at 1,373 people per square mile, while ZIP 98118 has 42,731 at 2,639 per square mile. That difference in population size and density alone reshapes how every other metric should be interpreted — a higher-income ZIP with 1,200 residents behaves very differently from one with 45,000.

On income and education, ZIP 98040 reports a median household income of $219,069 against $113,762 in ZIP 98118, with per-capita income of $128,615 vs $61,620. The share of adults holding a bachelor's degree or higher is 81.4% in 98040 and 51.9% in 98118. Poverty rate reads 3.8% vs 11.6%, and unemployment 3.0% vs 4.5% — these four fields alone drive most of the difference in the scorecard grades you will see for each ZIP.

Housing separates these two ZIPs further: median home value sits at $2,000,001 in 98040 versus $810,500 in 98118, with median rent of $2,502 and $1,839 per month respectively. Homeownership rate is 67.0% vs 57.1%. When reading the comparison table below, focus on paired metrics rather than single winners — a ZIP with lower home values and lower income is not strictly "worse" if rent-to-income ratios and commute times land in the same zone. Every value is pulled from the exact same ACS table so the two columns are genuinely comparable.