Right now NameCheap has the cheapest first year at $1.60, and Alibaba Cloud the cheapest renewal at $9.90. Over three years the lowest total at one registrar is $22.30 at Alibaba Cloud.
Why does .icu cost more after the first year?
Many registrars sell the first year below cost and recover it at renewal: at NameCheap, .icu renews at $17.98 after a $1.60 first year. Compare the renewal and 3-year columns before you buy.