Seattle's Tallest Buildings in the Pipeline

Seattle's skyline is still growing. Over a dozen towers above 39 stories are in the pipeline, nearly all of them in Downtown or South Lake Union. These are the tallest projects tracked by BuildVue, ranked by number of stories.

The Top 15

What the Data Shows

All 15 are in Downtown or South Lake Union. No other neighborhood in Seattle has the zoning capacity for buildings above 39 stories. Highrise (HR) zoning is limited to Downtown, South Lake Union, and small portions of First Hill and the Denny Triangle.

The tallest is 54 stories at 621 Stewart St. This Downtown tower is under construction with an estimated value of $178M. The permit shows zero residential units, suggesting it may be a hotel or commercial tower.

1,575 units at a single address. The South Lake Union project at 1101 Thomas St has the highest unit count of any project in the city at 41 stories and $213M in value.

Most are under construction, not planned. 13 of the 15 are actively under construction. Two have already completed. This wave of tower construction represents projects that secured financing before rates rose. Whether a similar wave of new tower starts will follow depends on financing conditions in 2026 and 2027.

Combined value exceeds $2.4 billion. These 15 projects alone represent about 13% of the city's total $18+ billion construction pipeline.

Where Tall Buildings Can Go

Seattle's highrise zoning allows the tallest buildings in a few areas:

• Downtown allows 400+ feet on some blocks
• South Lake Union allows 240 to 400 feet depending on the subarea
• First Hill allows up to 240 feet in parts of the neighborhood
• Denny Triangle allows 300+ foot towers

Outside these zones, heights cap at 85 feet (NC3 zones) or lower. A 40-story tower requires roughly 400+ feet, restricting these projects to the Downtown core.

The Economics of Towers

Buildings above 7 to 8 stories require concrete or steel structural systems instead of wood frame, which increases construction cost by 40 to 60 percent per square foot for the structure alone. Hard construction costs for a residential tower run $550 to $800+ per square foot, compared to $350 to $450 for wood-frame mid-rise.

That premium means towers need high rents or sale prices to pencil. Tower projects target the upper end of the rental market or the condo market. Affordable housing at tower scale requires deep public subsidies.

Track the Skyline

Sort projects by number of stories or construction value on BuildVue's map to find the tallest and largest projects in the pipeline.