When a lender performs a check, using a credit reference agency to view your credit report, or your credit score, it's known as a Credit Search. This differs from an Enquiry, as in every case it relates to the assessment of an application for credit.
The amount of information that the lender is able to see on a Credit Search depends entirely on the Principles of Reciprocity, which say that to receive a defined level of detail, the lender must report the same level of detail about all of its customers every month to a credit reference agency.
Most consumers have around 6-12 Credit Searches on their credit reports each year. Contrary to popular belief, a lot of Credit Searches do not severely impact your credit score, so you cannot be penalised for shopping around for credit. Conversely, a lot of Credit Searches undertaken in a very short period may be an indicator of fraudulent activity.
Credit Searches remain on your credit report for 1-2 years depending on the credit reference agency.