As a purchaser, you would often want fixed-rate. A variable rate is subject to the ups and the downs, but a fixed rate you can always refinance (at a cost, but one that's beaten out in the long-term by better average interest on a typical loan) to a lower fixed rate when available and ignore when rates climb. Since 30-yr loans are common, plans that play out on 5-10yr timescales are relevant. Given that banks are willing to offer them, you'd need an out-of-the-ordinary situation (selling soon, believing rates will continually decrease slowly, not being well educated, unique credit situation making rates favorable for one loan type and not another, ...) to choose a different option.