Generally, no — gift cards are close to cash equivalents, so retailers rarely apply percentage-off codes to them the way they would to physical products. A sitewide code might technically apply at checkout, but many retailers explicitly exclude gift card purchases from promotional codes; check the terms on the specific code before assuming it'll apply.
Free shipping offers are more likely to apply to a gift card order than a percentage-off code, since there's no physical shipping cost being discounted away either way. Bundle or dollar-off deals on a minimum spend sometimes apply, but percentage-off sitewide codes are the ones most commonly excluded — read the fine print on whichever code you're trying before checkout.
If getting more value into a gift card purchase matters to you, timing it around a major sale window (4/20, Black Friday/Cyber Monday) is generally more reliable than hunting for a code that applies to gift cards specifically — those windows sometimes include bonus-value gift card promotions that a standing coupon code wouldn't. Our newsletter flags new codes as we verify them, which is a more reliable way to catch a rare gift-card-eligible promotion than checking back manually.
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