Legal analysis: mortgage to buy a house requires that the age must be above 18, and the maximum age is not clearly defined. However, most banks stipulate that the borrower's age and loan period should not exceed 65, and individual banks should not exceed 70.

Legal basis: Article 7 of the Law of People's Republic of China (PRC) Commercial Bank, when a commercial bank conducts credit business, it shall strictly examine the credit standing of the borrower, implement the guarantee and ensure the timely recovery of the loan. Commercial banks recover the due principal and interest of loans from borrowers according to law, which is protected by law.