Newegg specialises in computer components, prebuilt systems and peripherals. It issues promo codes far more often than a general electronics retailer, and unusually those codes frequently stack with manufacturer mail-in rebates, which is the closest thing to genuine discount stacking in this category.

Codes here are narrow by design: a fixed amount off a single SKU or a single brand, valid for a short window. That makes them worth checking immediately before a purchase rather than collecting in advance.

Two cautions. Marketplace sellers are excluded from Newegg-issued codes even though their listings appear alongside first-party stock, so check who is selling before you count on a discount. And shipping on heavy items such as cases and monitors can undo a small code entirely.

1. Confirm the item is sold and shipped by Newegg, not a marketplace seller.
2. Click Get code and add the item in the Newegg tab.
3. Paste the code into the Promo code field at checkout.
4. Check whether a manufacturer rebate is also listed — those are claimed after purchase and stack with the code.