My wife's Yunnan hukou has been transferred to Tancheng Town, Mengcheng County, Bozhou City, Anhui Province. How to pay social security?

Just pay the security money in Bozhou that month.

As long as you have applied for a temporary residence permit for half a year, you can apply for settlement at any time. There used to be a three-year social security payment ceiling, but now it is unnecessary. As long as you pay in the current month, you can settle down.