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BT OSIS is a centrally administered telephone directory containing over 27 million individuals and businesses. It is updated 6 days a week and we ensure that any new records or changes be live and searchable within a few hours of receiving them.

Data8 offer services using this data, such as telephone appending whereby we can search BT OSIS to find telephone numbers for your records. The database is the only official directory of telephone numbers in the UK and is owned and administered by BT Directory Solutions (BTDS). It is the same data as used by the printed telephone directories and by the 118 directory operators.

When an individual requests a new telephone line and agrees to be listed in the telephone directory, the data will be entered into BT OSIS, making the BT OSIS database very accurate and up-to-date.

Data8 are licensed by BTWDS to hold an extract of the BT OSIS database and we can offer a variety of data cleansing services and technology to enable you to append appropriate telephone numbers to names and addresses that you already hold.

There are 3 different types of BT OSIS records that we hold:

  • Directory Entry (DE) - these are records that are listed in the printed phone books and held by the 118 operators. We can provide telephone number details for DE records.
  • Directory Query Restricted (DQR) - these records are not in the printed phone books but they are available on 118 services if you can uniquely identify them. We hold the DQR telephone numbers and can match them to your records when we make a unique match.
  • Ex-Directory (XD) - If we can uniquely match your name and address to an XD record we are able to confirm it as Ex-Directory.

Your Details on OSIS

Data8 holds an extract of the BT OSIS database but does not own or control this database. If you wish to remove or amend your personal details in the database then the only way that this can be achieved is to talk to your telephone provider: usually a company such as BT, TalkTalk or Virgin - the company that you pay your telephone bill to.

BT OSIS Forms part of our Append & Enhance Services. Click here for more information

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