How long do you have to be in the same line of work for home loan?

The general rule is two years, unless your work is related to an educational or trad school program, in which case you may be given credit for educational experience. If you have made a signicant change in your job career, the two-year rule may apply.

Generally 2 years, but FHA is looking more for a 2 year history not necessarily in same line of work. If you just graduated or went to school and received a degree or license you also don't need to have a 2 year history.