More than 1,090 people were caught watching TV without a valid licence in Derry in 2011, TV Licensing revealed this week.
This compares to more than 4,600 in Belfast, over 1,030 in Newry and more than 720 in Dungannon.
TV Licensing says it catches more than 1,000 evaders every day.
In all, there were more than 15,100 people caught watching TV illegally in Northern Ireland last year.
However, the estimated evasion rate remains steady at around 5%, as it has done for the last five years.
This means the vast majority of people, or 19 out of 20 households and businesses, are correctly licensed in accordance with the legal requirements.
Deborah King TV Licensing spokesperson for Northern Ireland, said: “TV viewing is as popular as ever, with the percentage of households who have a television set at 96.7%*, and it’s our role to make sure everyone is aware of when they need to be covered by a licence.
“On behalf of licence fee payers in Northern Ireland, we are committed to tackling evasion and enforcing the law amongst the small minority who should pay, but don’t.
“It’s only fair.
“People are given every opportunity to pay, but, if they fail to do so and watch TV illegally, we will seek a prosecution. The penalty is a fine of up to £1,000, plus court costs and a victim surcharge.
“Anyone found guilty is also required to buy a TV Licence at £145.50 if they still need one or they could face a second prosecution.
“It’s really not worth the risk.”
TV Licensing says it wants to make it as easy as possible for people to pay for a TV Licence. As such, it offers numerous ways to spread the cost, including Direct Debit and a weekly or monthly cash payment plan.
Information to help people decide which payment option will work best for them can be found on the TV Licensing website – www.tvlicensing.co.uk.