Brand Comparison · 2026

    LululemonvsAritzia, Size Comparison

    Aritzia tends to run smaller than Lululemon. If you wear a Medium at Lululemon, you may need a Large at Aritzia. For a measurement-based recommendation, use the fit checker.

    Quick Answer

    Lululemon vs Aritzia sizing, quick answer

    Aritzia runs about one size smaller than Lululemon. If you wear a Medium at Lululemon, you'll likely need a Large at Aritzia. For an exact recommendation, build a free fit profile.

    • Lululemon: fits true to size
    • Aritzia: runs small
    • If between sizes: size up at the brand that runs smaller, or use the fit checker below for a personalised recommendation.

    Brand guide

    Compare how Lululemon and Aritzia usually fit, where cuts feel slimmer or roomier, and which categories are most predictable.

    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.

    The Verdict

    Lululemon sizing compared to Aritzia: Lululemon fits true to size while Aritzia runs small. Here is how the sizes translate.

    Aritzia tends to run smaller than Lululemon. If you wear a Medium at Lululemon, you may need a Large at Aritzia. For a measurement-based recommendation, use the fit checker.

    LululemonTrue to size
    AritziaRuns small
    Lululemon brand mark

    Lululemon

    True to size

    Lululemon fits true to size in most styles. Size up if between sizes or for a relaxed fit.

    Aritzia brand mark

    Aritzia

    Runs small

    Aritzia runs small across most of its brands. Size up one, especially in TNA and Wilfred.

    Category Match-up

    Lululemon
    Aritzia
    Tops
    True to size

    True to size. Define jackets and fitted tops are snug by design.

    Runs small

    Runs small. Wilfred and Babaton are fitted, size up one.

    Bottoms
    True to size

    True to size. Align leggings are forgiving; Wunder Unders are more compressive.

    Runs small

    Runs small. Effortless pants size up one.

    Dresses

    No data for Lululemon Dresses

    Runs small

    Runs small. Fitted silhouettes, size up one.

    Outerwear

    No data for Lululemon Outerwear

    Runs large

    Puffers are oversized; size down for a tailored look.

    Activewear
    True to size

    Sizing is numerical (2–14). A 6 typically fits like a Small.

    No data for Aritzia Activewear

    Size Conversion Table

    Your SizeLululemonAritzia
    XXSXXSXS(Runs Small)
    XSXSS(Runs Small)
    SSM(Runs Small)
    MML(Runs Small)
    LLXL(Runs Small)
    XLXLXXL(Runs Small)
    XXLXXLXXXL(Runs Small)
    XXXLXXXLXXXL+(Runs Small)

    * Indicative only. For your personalised size at both brands,

    Common Questions

    Does Lululemon run smaller than Aritzia?

    Aritzia runs about one size smaller than Lululemon. If you wear a Medium at Lululemon, you'll likely need a Large at Aritzia. For an exact recommendation, build a free fit profile.

    Should I size up or down at Lululemon vs Aritzia?

    Size up one at Aritzia compared to Lululemon. Aritzia runs smaller, so if you wear a Medium at Lululemon, try a Large at Aritzia, especially for fitted tops and tailored bottoms.

    If I'm a Medium at Lululemon, what size am I at Aritzia?

    Since Aritzia runs smaller than Lululemon, a Medium at Lululemon is roughly equivalent to a Large at Aritzia. Use the ThisFits fit checker for a recommendation based on your measurements.

    Does Lululemon or Aritzia fit differently by category?

    Yes, fit varies meaningfully by category. Tops, Bottoms can each fit differently than the brand's overall tendency suggests. See the Category Match-up section below for per-category guidance.

    Which brand is more accurate to its size chart, Lululemon or Aritzia?

    Lululemon and Aritzia both publish official size charts, but real-world fit varies by fabric, cut and category. The ThisFits engine cross-references published charts with shopper fit reports across 197+ brands to predict your size in each.

    What if I'm between sizes at Lululemon and Aritzia?

    If you're between sizes, Aritzia tends to fit closer to the body, so trying the larger size first usually means fewer returns. Always confirm each retailer's return policy before ordering.

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    Your Personal Size

    See your size in Lululemon&Aritzia

    Build your fit profile once and see your likely size for Lululemon and Aritzia, based on your measurements.

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