This bed is amazing. I am undoing years of lumbar and cervical damage caused by a daily sedentary office reality. The mattress is firm. I wouldn't say xtra firm.  I've slept on firmer at upscale b&bs/hotels but it gives you a good nights sleep. It's gorgeous (I have a studio so aesthetics are important). You will need deep fitted sheets. I purchased a mattress cover that is twin extra long and it fits perfectly, covers the full depth