What is possessive form of banker?

Banker's

Explanation:

The object belongs to the banker

Therefore making it the banker's not the bankers

whenever an object belongs to someone or something use an apostrofy

The possessive form of banker is banker's. I think

Explanation:

A possessive noun shows ownership by adding an apostrophe, an "s" or both. To make a single noun possessive, simply add an apostrophe and an "s."