While the criteria for qualified health plans are the same nationwide for plans on the exchange, off exchange plans can vary by state.
Another difference is that off exchange coverage is only available through insurance companies and independent brokers. In contrast, on exchange insurance is offered through the government Marketplace or state-run marketplaces. In many cases, an insurance carrier will offer both an on exchange and off exchange plan with the same coverage. This is done to increase consumer choice.
On exchange plans also often require less out of pocket, as these plans are eligible for subsidies that substantially cut insurance costs. That is why a lot of people enjoy qualified health plans. On the other hand, subsidies are not available on off exchange plans.