Do Theory tops run small?

    Runs small

    Theory tops run small. Slim tailored cut. Size up 1 if between sizes.

    Need sizing help for Theory tops?

    Tops notes

    Get a personal size recommendation for Theory tops, accounts for the brand's cut tendency and your saved measurements.

    GENERAL BRAND GUIDANCE

    This is a general brand-level sizing summary, not an exact product recommendation. For your specific size, paste a product link into the fit checker.

    Theory Tops sizing

    Theory tops run small. Slim tailored cut. Size up 1 if between sizes.

    Best starting point

    Size up once in Theory tops if you want an easy everyday fit.

    Cut note

    Slim tailored cut.

    Examples

    Think tees, blouses, knits, and lightweight layering pieces.

    Which size should I buy?

    Default to sizing up in Theory tops if you want an easy everyday fit. Sizing stays consistent across Theory tops, so once you find your size it holds.

    Choose the slimmer feel

    Stay at your usual size only if you want a neater fit and feel comfortable in closer-fitting cuts.

    Choose the roomier feel

    Go up one size for breathing room, especially when this category uses closer-fitting cuts.

    Variability and caveats

    When Theory can feel different from the usual sizing tendency

    Cut

    Structured pieces usually feel smaller first, especially through the shoulders, waist, or hip.

    Fabric stretch

    Rigid fabrics usually make the sizing tendency show up more clearly because there is less give.

    Styling

    This brand is fairly consistent, but styling can still shift the feel when a piece is meant to be sharply fitted or deliberately oversized.

    Theory uses slim, modern tailoring patterns. Their blazers and trousers run about 1 size small compared to traditional US sizing.

    Theory Tops size chart

    Compare measurements side-by-side using the label rows below.

    Fit notes below call out cut and measurement differences that matter most on smaller screens.

    SizeBustWaistHipsEUUK
    XS
    		31–33"24–26"34–36"346
    S
    		33–35"26–28"36–38"368
    M
    		35–37"28–30"38–40"3810
    L
    		37–39"30–32"40–42"4012
    XL
    		39–41"32–34"42–44"4214

    Measurements are shown in inches where numeric values are available.

    Chart footnotes

    • Slim tailored cut

    Theory tops usually run small.

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