However, the next set of channels do cost if you have Sky. The "platform access cost" is £234, and for the full range of non-premium channels, it is £294 a year.
The Sky Sports channels (viewing share 2.7%) cost an extra £243 each year. The Sky Movies channels (viewing share 1.5%) costs an extra £192 a year.
However, the final 5.8% of viewing is of free-to-air channels:
Sky's charges to other broadasters
So, you would think that Sky would be very grateful to the public service broadcasters, because all their content is what people actually watch most of the time. All the public service broadcasts on satellite are using transponders the broadcasters have obtained directly from SES Astra - Sky do not own the satellites, they also rent their capacity from SES Astra.
EPG listing charge: £21,000 per TV channel per year, £16k per radio channel per year. The BBC list 11 TV channels excluding the 20 regional variations of BBC One and Two, and 18 radio channels. That's £231k for the non-regional plus £420k for the regional slots, and £288k for the radio stations, £939k total.
Then there's a 'Platform Contribution Charge' which seems to be set on viewership. For the BBC:
BBC Alba, BBC Parliament, BBC HD and BBC One HD presumably pay the £92k 'Other Television Channels' charge and the 18 radio stations the £6k charge. Total £9,887,625.
The BBC is probably paying Sky in the region of £11-12m for EPG services.
In most businesses, it is the business that has to pay for the data it uses. Newspapers don't charge the journlists for their reports. Marketing companies have to pay for address lists. You don't get paid a pound-a-minute for calling 118118. How Sky get away with this outrage is a very good question.