Legally, yes: the law does not prevent or bar an employer from also being a customer of the employee's business. You can legally be employee and vendor at the same time.Of course, this might be against the bank's policy. And if you fail to disclose your dual role to them and they later find out, if they feel that you cheated them in some way (e.g. were effectively double paid for the same work, by being paid as a vendor or contractor to work on the same project you were being paid as an employee, without disclosing that and getting it approved; or used your position as employee to "steer" work to your own busness or to overcharge the employer) you could be sued. This is legal *as long as* your dual role is disclosed and the bank approves it (preferably in writing, so it can be proven later at need) after disclosure. A failure to disclose makes you potentially liable for fraud, theft of time (being paid for work you didn't do as an employee, since you did it as a vendor), or one a similar basis. So disclose everything and get it approved; then you are ok.