Most insurance companies have open enrollment periods and that is the only time you can add dependents unless there is a qualifying event (like marriage, adoption, birth). So if your husband was to lose his job, you could still be without insurance until the open enrollment period at your place of business. At our company, July is our enrollment month. We've, unfortunately, had to inform some of our employees, about this when they thought they could just add at any time. Insurance companies do not consider loss of other coverage as a qualifying event.