Your guess is a good as mine, this is the issue with the opaque nature in which insurers operate. EU law changed they way insurers operate due to the Equalities Act, so they can't positively discriminate based gender like they used to, i.e. women being deemed to be less risk. If anything, as you have mentioned, your premium should be higher. Does your husband have any claims or convictions in the last five years? It's either that or your husband's occupation. Try changing everything so it's identical.