The lender is also giving up to £500 cashback on select remortgage products taken through advisers.
The changes will help customers with the expenses of buying a house and allow brokers to access more competitive deals, NatWest said.
Mark Bullard, head of sales at the lender, added: “The launch of free valuations strengthens our proposition within our intermediary exclusive purchase range.
“Along with this, we are now able to strengthen our remortgage proposition by offering a cashback incentive to complement our current existing free legals and valuation features.”
At the same time, the lender has changed rates on a number of two and five-year products across its purchase, remortgage and buy-to-let ranges.