An 11×17 picture fits an 11×17 frame with no mat; once you add a mat, the outer frame usually grows to 16×20 or 18×24.
A poster you love comes home from the print shop, you order a frame that says 11×17 on the label, and the print still won’t drop in cleanly. That gap between the frame’s outside measurement and its inside opening is where most framing mistakes happen. What size frame you need for an 11×17 picture comes down to one fork in the road: framing the print bare, or framing it with a mat. Those are two different frame sizes, and mixing them up is the single most common error.
This guide gives you both numbers, names the gate that trips people up, and ends with a table you can screenshot before you buy.
Without a Mat, the Frame Size Matches the Print
An 11×17 print needs an 11×17 frame when you skip the mat, because standard picture frame sizes are measured by inside dimensions. Frame USA lists 11×17 as a standard frame size and states that its frames are measured by inner dimensions, which means an 11×17 frame is built to hold an 11×17 image.
Two caveats matter here. First, that’s the opening, not the outer edge — a frame labeled 11×17 has an exterior that’s larger than 11×17. Second, some ready-made frames have a slightly smaller actual display area because of border overlap or the rabbet, the recessed lip that holds the glass and backing. Your print may not show edge-to-edge exactly as you pictured it.
With a Mat, the Frame Grows
An 11×17 print with a mat typically needs a 16×20 frame, and 18×24 is another common landing spot, depending on mat width and how wide a border you want.
Frame Destination is direct about it: an 11×17 print needs an 11×17 frame without a mat, or a 14×20 with a mat. The Southern Arizona Watercolor Guild’s mat guide lists 11×17 prints moving into an 18×24 outer mat-board arrangement. Those numbers don’t conflict so much as they describe different mat borders — a narrow mat keeps you closer to 16×20, a wider one pushes toward 18×24.
The math is simple once you see it. A 4-inch mat border adds 8 inches to each dimension, turning an 11×17 opening into roughly 19×25 of mat board, which then needs an even larger outer frame. A 2-inch border adds 4 inches per side, keeping you nearer the 16×20 or 18×24 range.
The Measurement That Decides Everything
Terminology is the trap. Product listings swap between “frame size,” “inner dimensions,” “display area,” and “mat opening” as if they mean the same thing, and they don’t. Before you buy:
- Unmatted frame: the inside opening must read 11×17, or a hair larger to account for the rabbet.
- Matted frame: the mat opening must be 11×17, and the outer frame will be bigger than that.
- Sale listings: check whether the listed size describes the outer frame or the opening — a “16×20 frame” with a pre-cut mat may open to 11×17 or to something else entirely.
If you’re replacing a mat or buying a frame for a print you already own, measure the print itself with a tape measure rather than trusting the print label. Trimming differences of an eighth of an inch are normal in poster printing.
When you’re ready to compare options, our roundup of the best 11×17 picture frame picks covers tested frames in both unmatted and matted configurations.
Quick Size Reference
| Setup | Frame Size Needed | Watch Out For |
|---|---|---|
| No mat | 11×17 | Inside opening, not outer edge |
| Narrow mat border | 16×20 | Confirm the mat opening reads 11×17 |
| Narrow mat, Frame Destination spec | 14×20 | Minor image overlap at the lip |
| Standard mat border | 18×24 | Measure the border you actually want |
| Pre-matted ready-made frame | Varies | “Frame size” may mean outer dimensions |
| Ready-made 11×17 frame | 11×17 | Rabbet overlap can clip the edges |
| Custom frame | Your exact opening | Give the framer the mat opening size |
The guide to frame and mat dimensions for common print sizes from Frame Destination is the clearest public reference if you want to double-check your specific setup against a second chart. Frame and mat dimension chart
FAQs
Will an 11×17 print fit a 16×20 frame without a mat?
No. A 16×20 frame’s inside opening is 16×20, so an 11×17 print will rattle around with visible gaps unless you add a mat cut to an 11×17 opening. If you want the print to sit flat against the glass with no mat, buy an 11×17 frame instead.
Can I put an 11×17 print in an 18×24 frame?
Yes, with a mat. An 18×24 frame is a common outer size for an 11×17 print paired with a mat board cut to an 11×17 opening. Without a mat, the print would sit loose in the frame with a wide empty border.
How do I know if a frame is measured by inside or outside dimensions?
Check the listing’s spec sheet or product photos for terms like “inner dimensions,” “mat opening,” or “display area.” Frame USA notes its frames are measured by inside dimensions. If a listing only gives an outside measurement, assume the opening is smaller and measure before buying.
References & Sources
- Frame USA. “Picture Frame Sizes” Confirms 11×17 as a standard size measured by inside dimensions.
- Frame Destination. “Guide to Frame and Mat Dimensions for Common Print Sizes” Lists 11×17 without mat and 14×20 with mat.
- Southern Arizona Watercolor Guild. “Adjusting Mat Sizes for Standard Frame Sizes” Lists 11×17 within an 18×24 outer mat-board arrangement.
