Type how wide you want the opening. You get it drawn on your wall, the sill and the ledge, how many stools fit, what the building code asks above it, and what it costs.
Your pass-through
A 48″ × 18″ opening, its sill at 36″12″ serving ledge · $500–$1,500 if the wall is not load-bearing, $2,200–$5,500 if it is
Your wall: its length, the top, the ceiling
Measure the wall's thickness at a doorway.
Quick answer: set a kitchen pass-through’s sill at 36 inches, level with the counter, and make it 36 to 72 inches wide. A serving ledge is at least 12 inches deep, and 15 inches or more if people will sit at it (Block Renovation, 2026). Each stool gets 24 inches of ledge (NKBA). In a wall that is not load-bearing the building code asks for no load-bearing header; in a load-bearing one an engineer designs it. The planner draws it on your wall.
How to use the pass-through planner
- Type the opening’s width. It is drawn centered on your wall, to scale.
- Pick the sill: counter height (36″) continues the kitchen counter through the wall; a bar ledge (42″) stands a step above it.
- Serving or stools? Stools on the other side need a deeper ledge, and the planner counts how many fit.
- Say whether the wall is load-bearing, or “unsure” to see both answers. The load-bearing wall checker walks you through the clues.
- Open “Your wall” under the answer to set the wall’s length and thickness (measure it at a doorway), where the opening ends and your ceiling height.
- Read the result: the opening drawn on your wall and the ledge from the side, the stools, what the code asks above the opening, and the cost. Copy link keeps your answers.
The size, from the people who build them
Block Renovation’s guide gives the numbers in one sentence: “Set the sill at 36 inches to align with standard counters. Widths usually range from 36 to 72 inches, sized to fit between studs and any utilities you want to leave in place. A serving ledge should be at least 12 inches deep, and 15 inches or more if you want seating.”
The planner measures the ledge from the kitchen face of the wall: your wall’s own thickness, plus what reaches past it into the other room. For stools, it reaches past the wall by the knee space the NKBA’s Kitchen Planning Guidelines give at that height, and never less than Block’s 15 inches in all.
| Sill | Stool to buy | Width per stool | Knee space past the wall | Ledge with a 4½″ wall |
|---|---|---|---|---|
| Counter height, 36″ | 24″ counter stool | 24″ | 15″ | 19½″ |
| Bar ledge, 42″ | 30″ bar stool | 24″ | 12″ | 16½″ |
The stool heights are the bar stool height calculator‘s answer at those heights: the seat 10–12″ below the underside of the top.
How many stools fit
| Opening width | Stools (24″ each) |
|---|---|
| 36″ (3 ft) | 1 |
| 48″ (4 ft) | 2 |
| 60″ (5 ft) | 2 |
| 72″ (6 ft) | 3 |
What the building code asks above the opening
In a wall that is not load-bearing, the International Residential Code (2021, R602.7.4) says: “Load-bearing headers are not required in interior or exterior nonbearing walls. A single flat 2-inch by 4-inch (51 mm by 102 mm) member shall be permitted to be used as a header in interior or exterior nonbearing walls for openings up to 8 feet (2438 mm) in width if the vertical distance to the parallel nailing surface above is not more than 24 inches (610 mm).” The planner checks both numbers: your opening’s width, and the space between its top and the ceiling.
In a load-bearing wall, the opening needs a real header. “Headers shall be supported on each end with one or more jack studs” (R602.7.5), and Block’s guide adds that “A structural engineer can confirm and, if needed, design the header that will carry the load across the new opening”, with temporary supports while it goes in. The planner never sizes a header for a bearing wall: that is the engineer’s job.
Your city adopts the code with its own changes, and Block notes that most cities count a new opening as a structural change that needs a permit. The remodel permit checker lists the rest of your jobs.
What a pass-through costs
| The job | Cost |
|---|---|
| An opening in a wall that is not load-bearing | $500–$1,500 |
| The same, with wiring or other utilities rerouted | $1,000–$2,500 |
| An opening in a load-bearing wall (shoring, header, framing, finish) | $2,200–$5,500 |
| The structural engineer, billed separately | $300–$800 |
| Permit fees | $100–$500 |
All from Block Renovation’s 2026 guide, which also warns that “A vent stack in the middle of your planned opening can add $1,000 or more in rerouting, or force you to shift the opening over.”
Four worked examples
A serving window under the wall cabinets. A 48″ × 18″ opening, its sill at 36″, with a 12″ ledge. It stops at 54″, so wall cabinets hung 18″ above a 36″ counter can stay above it. With an 8-foot ceiling, the framing above is 42″ up, more than the 24″ the single-flat-2×4 option allows, so the builder frames that space another way. About $500–$1,500.
The same opening with stools on the living-room side. A 48″ × 18″ opening, its sill at 36″: a 19½″ ledge (the 4½″ wall plus 15″ of knee space) and two 24″ counter stools.
A 6-foot bar. A 72″ × 24″ opening, its sill at 42″: a 16½″ ledge (12″ of knee space at bar height past the wall) and three 30″ bar stools.
A tall opening in a load-bearing wall. A 60″ × 44″ opening, its sill at 36″, up to door height. It needs an engineered header on jack studs: $2,200–$5,500 for the work plus $300–$800 for the engineer.
Common pass-through mistakes
- Cutting before looking inside. Block calls kitchen walls “the most crowded walls in the house”: circuits, supply lines, drain and vent stacks, ducts. A contractor often opens a small inspection hole first.
- Guessing whether the wall is load-bearing. A wall under a beam or a wall above, or across the floor joists, is likely structural. The engineer’s visit costs far less than a sagging ceiling.
- A ledge too shallow for stools. 12″ holds plates; knees need 15″ past the wall at counter height.
- A small, heavily trimmed cutout. Block notes that the narrow, heavily trimmed pass-throughs of the 1970s and 80s are why some buyers wince at the word. Wider, barely trimmed openings read as an upgrade.
- Choosing a pocket panel too late. A panel that slides into the wall needs a cavity free of studs, wiring and plumbing: decide before the wall is framed.
Kitchen pass-throughs: questions people ask
How big should a kitchen pass-through window be?
Block Renovation puts the sill at 36 inches, level with the counters, and the width at 36 to 72 inches, sized to fit between studs and any utilities you keep. A serving ledge is at least 12 inches deep, 15 or more for seating.
Do you need a header for a kitchen pass-through?
In a load-bearing wall, yes: a header on jack studs, designed by an engineer. In a wall that is not load-bearing, the IRC (R602.7.4) requires no load-bearing header, and lets a single flat 2×4 serve for an opening up to 8 feet wide when the framing above is no more than 24 inches higher.
How much does a kitchen pass-through cost?
About $500–$1,500 in a wall that is not load-bearing ($1,000–$2,500 if wiring or pipes move), and $2,200–$5,500 in a load-bearing wall plus $300–$800 for the engineer, with permits often $100–$500 (Block Renovation, 2026).
Pass-through or half wall between the kitchen and living room?
A half wall takes away everything above roughly 36 to 42 inches, so the rooms read as one, but the wall cabinets on it go too. A pass-through keeps the wall, its cabinets and some separation from the kitchen mess and noise (Block Renovation).
How many stools fit at a pass-through?
One stool for every 24 inches of ledge (NKBA): a 4-foot opening seats two, a 6-foot one three.
Do you need a permit for a pass-through window?
Usually: most cities count cutting a new opening in a wall as a structural change, and a load-bearing wall always needs a permit, engineering documents and inspections (Block Renovation). Ask your city’s building department.
Read next
- A real whole-home plan, before and after: two walls down, room by room
- What makes open concept living rooms so appealing
- Kitchen and living room combo ideas
- Kitchen nook ideas
- Wood slat room dividers for an open plan
Want to see the whole kitchen first? Draw it to size in the free 2D planner.
Sources, read October 15, 2026: Block Renovation, “Adding a Pass Through Window to Your Kitchen” (David Rudin, June 12, 2026, updated June 26, 2026); the International Residential Code 2021, R602.7.4 and R602.7.5 (UpCodes’ copy of Colorado’s code, which adopts the IRC 2021 without amendments); the NKBA Kitchen Planning Guidelines, Guideline 9 (Seating Clearance). Prices change: this page is re-checked every six months.