Agentis analysis shows a 'Buy One Get One 50% Off' promotion applies its discount to only one of the two units purchased, making the effective discount rate on the full purchase 25%, not the 50% the headline implies. On two $40 items, the customer pays $60 total instead of $80, half the savings a shopper skimming the ad might expect.
The regular price of one unit.
100% means the second item is fully free.
Total Paid for Both Items
$60.00
Effective Discount on the Full Purchase
25.0%
| Discount Type | Applies To | Stacking Restriction |
|---|---|---|
| Buy X Get Y (BOGO) | A qualifying item and a discounted or free item | On non-Shopify-Plus stores, every product in the BOGO offer becomes ineligible for any further product discount |
Source: Shopify Help Center: Combining discounts (retrieved August 7, 2026). This restriction is specific to Buy X Get Y discounts and doesn't apply to standard percentage-off or fixed-amount product discounts, which can combine across different items even on non-Plus stores.
| Framing | Total Paid | Effective Discount |
|---|---|---|
| Buy One Get One 25% Off | $70.00 | 12.5% |
| Buy One Get One 50% Off | $60.00 | 25.0% |
| Buy One Get One Free | $40.00 | 50.0% |
| Buy 2 Get 1 Free (3 units) | $80.00 | 33.3% |
Source: Shopify Help Center: Combining discounts (retrieved August 7, 2026). Agentis synthesis: pure arithmetic on each BOGO framing at a $40 per-item price, showing the effective discount across the full purchase rather than the headline percentage.
How we calculate this
Shopify's own documentation confirms Buy X Get Y as a distinct discount type with its own stacking rules, separate from standard product discounts. The effective-discount-rate figures are Agentis synthesis: straightforward arithmetic dividing total savings by total purchase price for each common BOGO framing. Read our full methodology →
Expert Insight
BOGO framing is built to be read faster than it's calculated. 'Buy One Get One 50% Off' sounds like half-price shopping. It's a 25% discount on the actual purchase, because the discount only ever touches one of the two units. Merchants get this backwards in both directions: sometimes underestimating the real cost because the headline number looks smaller than it is, sometimes overestimating how much margin a BOGO promotion protects compared to a straight percentage-off code. Know the effective rate before you approve the promotion, not after the sales report shows the actual margin hit.
Herzel Mishel, CEO & Co-Founder →Only if the customer buys items in pairs. The discount applies to just one item in each pair, so the effective rate across that purchase works out to 25%. A single-item purchase, or an odd number of items, doesn't get any BOGO discount on the unpaired unit at all.
Agentis analysis of Shopify's own documentation confirms a customer can stack up to 5 product or order discount codes plus 1 shipping code, 6 total, on one order. Each code applies to the already-discounted subtotal, not the original price, so five stacked 10% codes cut the price by 41%, not the 50% naive addition suggests.
Agentis analysis of Shopify's own discount-combination documentation confirms an order-level discount code combines with a free-shipping discount by default, no special setup required. On an $80 order with 40% gross margin, a 20% discount code cuts gross profit from $32 to $16, and stacking an $8 shipping cost on top drops it to $8, a 75% cut in what the order was expected to earn.
Agentis finds margin leaks automatically.
Data last updated August 7, 2026. Browse all Discounts & Promotions pages →