Free Storage? Paid Plans. 2 per month for 100GB of storage -$70 a year ($7 per month) for 1TB of storage. Microsoft 365 Family offers a 1-month free trial, then costs $100 a year ($10 per month). Family package offers 6TB of storage. 20 a month for one user with 3TB of storage. 15 a month for 5TB of space for Teams -$25 a month for customizable team storage.