The San Francisco 49ers have a ton of cap space in 2018, and that number will grow with a sizable the chunk the team will be able to roll over from 2017. The NFL and NFLPA will at some point announce how much 2017 salary cap space each team will roll over into the 2018 league year. This year, the NFLPA’s public salary cap report suggests the 49ers could have $56,048,430 in cap space to roll over.
The NFLPA announced on January 18, 2017 what cap space would be rolled over from 2016. They have not yet announced the official numbers for this year, but we should find out in relatively short order.