Howdy Wadud, thanks for reaching out to ask us your question about the Samsung Galaxy S25 Ultra. The advertised unlocked Galaxy S25 Ultra is the U.S. version of this device. It is compatible with the following U.S. wireless carriers: AT&T, Boost Mobile, Cricket, Google Fi, H2O Wireless, Mint Mobile, Sprint, T-Mobile, Ultra Mobile, US Cellular, Verizon, and Visible. Please contact a compatible carrier to inquire if Bangladesh is within their serviceable region. If you have additional questions, do not hesitate to contact Support. Thank you for being a faithful Samsung customer. - Debra