The latest price tag for renovating City Hall is approaching $107 million — making it more expensive than the Tweed Courthouse project, which came in at nearly three times its original estimate a decade ago, The Post has learned.

In November, The Post reported that it would cost about $90 million to make major structural repairs to the 200-year-old building and to install modern mechanical systems.

Officials said costs escalated sharply after construction crews discovered more serious structural deterioration than anyone had anticipated.