Do I have to put 20% down to buy a house?

No, you do not need 20 percent down. Many loan programs require much less. Conventional loans can go as low as 3 percent down for qualified buyers. FHA loans require a minimum of 3.5 percent down. VA loans for eligible veterans and active military require zero down, as do USDA loans for qualifying rural properties and buyers. The tradeoff is that putting down less than 20 percent typically means you will pay mortgage insurance, either PMI on conventional loans or MIP on FHA loans, which increases your monthly payment. How much you should put down depends on your finances, loan type, and how you want to balance upfront cost against monthly payment and long term interest.