Mercury Holidays is offering a price promise for all tour bookings to more than 50 countries.
The Tour Price Promise means the operator will refund the difference if it drops the price of the tour after a customer has already booked.
Mercury said: “This means early bookers are always safe in the knowledge they’re getting our best possible price.”
It added the tour must be “like-for-like” including departure date, outbound airport and any extras booked, plus flight costs are not included in the price promise if they are alternative flights.
If the price reduction is made before the final balance is paid, then the discount will be taken off the final balance charge, Mercury added.
The price promise does not include river cruise and package holiday bookings.
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