Though there are many variations, HMO (Health Maintenance Organizations) plans typically enable members to have lower out-of-pocket healthcare expenses but also offer less flexibility in the choice of physicians or hospital than other health insurance plans. As a member of an HMO, you'll be required to choose a primary care physician (PCP). Your PCP will take care of most of your healthcare needs. Before you can see a specialist, you'll need to obtain a referral from your PCP.
With an HMO you'll likely have coverage for a broader range of preventive healthcare services than you would through another type of plan. You may not be required to pay a deductible before coverage starts and your co-payments will likely be minimal. With an HMO plan, you typically won't have to submit any of your own claims to the insurance company. However, keep in mind that you'll likely have no coverage whatsoever for services rendered by non-network providers or for services rendered without a proper referral from your PCP.