Mango and Primark sit at opposite ends of the reliability spectrum. Mango is the most true-to-size of the Spanish high-street brands, with a published EU/alpha chart its garments actually follow. Primark sizes in UK numbers, runs small — most sharply in denim and anything fitted — and is famously inconsistent garment to garment.
The charts disagree too, not just the garments. Line the two up at the same UK size (Mango publishes UK conversions) and Primark's body measurements come in smaller at every single row, with the gap widening as sizes go up — because Mango grades generously above S while Primark's steps stay tight. Below are both charts aligned, the women's mapping that actually works, and the men's chart, where the two brands surprisingly agree.
The short answer
Primark runs smaller — on the chart and in the garment
For women, this one is clear-cut. At a nominal UK 12, Mango's L fits a 98 cm (38.6") bust while Primark's 12 fits 91 cm (36") — a full size of daylight, and the gap grows from there: at UK 16, it's Mango's 110 cm against Primark's 102 cm. By body measurement, your Mango size corresponds to roughly one UK size up at Primark — a Mango M (92 cm bust) matches Primark's UK 12 (91 cm), not the UK 10 that Mango's own conversion suggests.
Then add fit behavior on top. Mango garments deliver what the chart promises; Primark's tend to run small against their own chart — staff famously recommend sizing up in denim — and consistency between identical garments is loose. The practical rule: convert your Mango size up one UK number, and go up another in Primark jeans, fitted dresses, and tailored shirts. Men's sizing is the exception — the two brands' chest charts align well by letter.
Mango vs Primark at a glance
| Mango | Primark | |
|---|---|---|
| Sizing system | EU-based with alpha labels (XS–XXL) as primary | UK numeric sizing (women); alpha sizes for men |
| Overall fit | True to size — the dependable Spanish brand | Runs small, especially denim and fitted pieces |
| Consistency | Reliable — chart and garment agree | Famously loose — two identical items can fit differently |
| Where to size up | Fitted woven dresses and jeans only | Jeans, fitted dresses, and formal shirts — standard advice |
| Chart grading | Steps widen above S — L and XL run roomy | Tight, even steps from UK 4 to 20 |
Mango letters mapped to Primark UK sizes (women)
Aligned by bust measurement, not by Mango's official UK conversion — by body, each Mango size lands about one UK number higher than the conversion suggests.
| Mango size | Mango bust | Closest Primark size | Primark bust |
|---|---|---|---|
| XS | 82 cm · 32.3" | UK 8 | 83 cm · 32.5" |
| S | 86 cm · 33.9" | UK 10 | 87 cm · 34.5" |
| M | 92 cm · 36.2" | UK 12 | 91 cm · 36" |
| L | 98 cm · 38.6" | UK 14 | 96 cm · 38" |
| XL | 104 cm · 40.9" | UK 16 | 102 cm · 40" |
| XXL | 110 cm · 43.3" | UK 18 | 109 cm · 43" |
Same nominal UK size, different body (women)
Bust and waist at the same UK label, using Mango's official UK conversion. Primark's chart is smaller at every size, and the gap widens going up.
| UK size | Mango bust | Primark bust | Mango waist | Primark waist |
|---|---|---|---|---|
| 8 | 86 cm · 33.9" | 83 cm · 32.5" | 66 cm · 26" | 66 cm · 26" |
| 10 | 92 cm · 36.2" | 87 cm · 34.5" | 72 cm · 28.3" | 70 cm · 27.5" |
| 12 | 98 cm · 38.6" | 91 cm · 36" | 78 cm · 30.7" | 74 cm · 29" |
| 14 | 104 cm · 40.9" | 96 cm · 38" | 85 cm · 33.5" | 79 cm · 31" |
| 16 | 110 cm · 43.3" | 102 cm · 40" | 92 cm · 36.2" | 85 cm · 33.5" |
Men's tops side by side
Chest measurements by letter — Mango publishes single body values, Primark publishes to-fit ranges. Unlike the women's charts, these align well.
| Size | Mango chest | Primark chest |
|---|---|---|
| XS | 87 cm · 34.3" | up to 36" · 90 cm |
| S | 95 cm · 37.4" | 36–38" · 91–96 cm |
| M | 101 cm · 39.8" | 38–40" · 97–102 cm |
| L | 107 cm · 42.1" | 41–43" · 103–108 cm |
| XL | 113 cm · 44.5" | 44–46" · 112–117 cm |
Switching between Mango and Primark
- Going Mango → Primark (women): take one UK size above what Mango's conversion says — a Mango M shops as a Primark 12, not a 10 — and go up another in Primark denim and fitted styles.
- Going Primark → Mango: most people drop a size. If Primark's UK 12 fits you, Mango's M (nominally a UK 10) covers the same body.
- Men can keep their letter in both stores — the chest charts align — but remember Primark consistency varies, so check the garment label.
- Primark's chart is a starting point, not a guarantee: garment-to-garment variation is the brand's defining trait, so when fit matters, check the measurements on the label.
Measurements are based on each brand's published size charts and may vary by garment, fabric, and region. For the full charts and fit notes, see the Mango size guide and the Primark size guide.
Mango vs Primark sizing FAQs
Which runs smaller, Mango or Primark?
Primark, by a clear margin for women. Its chart measures smaller than Mango's at every converted size — 91 cm bust at UK 12 versus Mango's 98 cm — and its garments additionally tend to run small against that chart, especially jeans and fitted dresses. Mango is true to size.
What Primark size should I buy if I wear a Mango M?
A Primark UK 12. Mango's M fits a 92 cm (36.2") bust, which matches Primark's UK 12 (91 cm) almost exactly — even though Mango's official conversion calls its M a UK 10. For Primark jeans or anything fitted, consider the 14.
Why does the gap between the two brands grow at larger sizes?
Mango's size steps widen above S — each size up adds more room than the one below — while Primark's chart climbs in tight, even steps. At UK 8 the bust difference is 3 cm; by UK 16 it's 8 cm. The bigger the size, the more sizing up at Primark matters.
Do Mango and Primark men's sizes match?
Better than the women's charts do. Mango's M (101 cm · 39.8" chest) sits inside Primark's M (38–40"), and L and XL align too. Keep your letter — but Primark's looser garment consistency still applies, so fitted shirts may warrant a size up.
Is Primark's sizing reliable enough to order by chart?
Treat it as a starting point. Primark revised its chart in 2021 after complaints, but shoppers still report a smaller-than-labeled tendency in fitted styles, and two identical garments can measure differently. Mango is the safer brand to buy unseen; at Primark, check the label's measurements.
