Looking to extend your subscription even further into the future? Microsoft doesn't advertise it, but you can in fact stack up codes in order to subscribe for multiple years. Just buy two or more cards, and revisit the activation page to enter the codes for each one. After submitting each, you'll see your subscription extended by another 12 months.
For example, I bought three product-key cards from Amazon for a total of $216.30. Figuring in the free trial I mentioned, that comes out to $5.85 a month for three years of Office 365 Home. Or you can buy one year, and then keep an eye out for a good deal on a product key card in the future — you can add its code to extend your subscription at any time while your subscription is active.
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