Free channels:
Galaxy (entertainment)
Now (factual and lifestyle)
The Power Station (music)
The Sports Channel (sports)

£10 per month (2019 adjustment: £23):
The Movie Channel (movies)

The Computer Channel was also available between 28th of June and 29th of November 1990, but was intended for business users (as part of BSB’s Datavision service) rather than home users.

Viewing BSB services required a D-MAC receiver and a suitable small dish or “Squarial”.
These were not compatible with Sky’s PAL service.

The fate of the channels post-merger with Sky Television plc was as follows:
Galaxy: replaced with Sky One on 2nd of December 1990
Now: replaced with Sky News (with BSB-specific opt-outs to broadcast Sky Arts) on 1st of December 1990
The Sports Channel: rebranded to Sky Sports on 20th of April 1991
The Power Station: replaced by Sky Movies Plus on 8th of April 1991, free for the second half of April 1991 for existing The Movie Channel subscribers but £9.99 thereafter (or £14.99 with The Movie Channel)
The Movie Channel: remained on air even beyond the discontinuation of the D-MAC service as a PAL channel until 1997 when it was branded as Sky Movies Screen 2, also free to Sky Movies subscribers for the second half of April 1991 as with Sky Movies Plus for The Movie Channel subscribers but £9.99 thereafter (or £14.99 with Sky Movies Plus)

For more information on the post-merger channel lineup (from May 1991 onwards), please see BSkyB lineup for May 1991.