A southern Chinese city is requiring couples to pay an $850 deposit for a marriage license to enforce the national one-child-per-couple population policy.

The deposit collected in Guangzhou, near Hong Kong, will be returned after 14 years if the couple has only one child, the Xinmin Evening News reported Monday.China is trying to restrain the growth of its population of 1.2 billion people by limiting most families to one child. Violators can be fined or lose their jobs or homes.

But couples are finding it easier to flout the rules because of increased private employment and rising incomes, especially in Guangzhou and other booming coastal areas.