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. On two $40 items, the customer pays $60 instead of $80. The same arithmetic shows how framing changes the real rate: Buy One Get One 25% Off is a 12.5% effective discount, Buy One Get One Free is 50%, and Buy 2 Get 1 Free across three units is 33.3%. Shopify treats Buy X Get Y as its own discount type, and on non-Plus stores every product in the offer becomes ineligible for any further product discount, which limits how far a BOGO can stack. Before approving a BOGO promotion for your store, divide the total savings by the total purchase price to get the effective rate, then compare that against the margin on the SKUs included.
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 →