Brand Comparison · 2026

    SimonsvsOld Navy, Size Comparison

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

    Quick Answer

    Simons vs Old Navy sizing, quick answer

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

    • Simons: fits true to size
    • Old Navy: runs large
    • 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 Simons and Old Navy 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

    Simons sizing compared to Old Navy: Simons fits true to size while Old Navy runs large. Here is how the sizes translate.

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

    SimonsTRUE TO SIZE
    Old NavyRUNS LARGE
    Simons logo

    Simons

    TRUE TO SIZE

    Canadian sizing, generally true to size with relaxed proportions

    Old Navy logo

    Old Navy

    RUNS LARGE

    Generous American sizing, runs large

    Category Match-up

    Simons
    Old Navy
    Tops
    TRUE TO SIZE

    True to North American size. Twik fits closer; Contemporaine is relaxed; ICÔNE is trendy/slim.

    RUNS LARGE

    Generous, relaxed cuts. Runs large. Size down for a fitted look.

    Bottoms
    TRUE TO SIZE

    Reliable waist and hip sizing. Inseam lengths run standard.

    RUNS LARGE

    Jeans run large with a roomy seat. Rockstar jeans are the exception, those run slim.

    Dresses
    TRUE TO SIZE

    True to size. Maison Simons dresses are cut generously through the hip.

    No data for Old Navy Dresses

    Activewear

    No data for Simons Activewear

    RUNS LARGE

    PowerSoft and Go-Dry leggings run large. Size down for compression.

    Size Conversion Table

    Your SizeSimonsOld Navy
    XXSXXS<XXS(Runs Large)
    XSXSXXS(Runs Large)
    SSXS(Runs Large)
    MMS(Runs Large)
    LLM(Runs Large)
    XLXLL(Runs Large)
    XXLXXLXL(Runs Large)
    XXXLXXXLXXL(Runs Large)

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

    Common Questions

    Does Simons run smaller than Old Navy?

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

    Should I size up or down at Simons vs Old Navy?

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

    If I'm a Medium at Simons, what size am I at Old Navy?

    Since Simons runs smaller than Old Navy, a Medium at Simons is roughly equivalent to a Small at Old Navy. Use the ThisFits fit checker for a recommendation based on your measurements.

    Does Simons or Old Navy 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, Simons or Old Navy?

    Simons and Old Navy 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 Simons and Old Navy?

    If you're between sizes, Simons 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.

    More Comparisons

    Your Personal Size

    See your size in Simons&Old Navy

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