They can act as guarantors
If your parents can't help you with the deposit, they may be able to act as guarantors for you instead. This means that if you are unable to make the mortgage payments, your parents guarantee to pick up the bill.
However it’s worth remembering that your parents would be providing additional security, which will be at risk if you default on the mortgage. Whilst parents are keen to assist their children in getting on the property ladder, it shouldn’t necessarily be done at the expense of their financial security or indeed their standard of living.
Help with a family offset mortgage
Another option is a "family offset" mortgage where parents use their savings to help their children or grandchildren on to the property ladder. These deals allow you to retain ownership of the money that you put up for a deposit.
The advantage is that the savings remain in the name of the parents and can revert to them at a later date. With this type of deal, you put your cash into a linked savings account. The money acts as a deposit and will lower the monthly mortgage repayment, as interest is charged only on the balance remaining.