More than 700 people owe a combined total of £28,000 in unpaid litter fines in Southampton.
The city council issued 2,144 fines between 23 June and 19 October, but hundreds are still to be paid.
The authority said the number of outstanding fines was expected to go down as late payments were made and prosecutions were concluded.
By Amy Gladwell
A recycling trial in Whitehead, County Antrim, is paying residents 20p for each used plastic bottle they place into their household recycling bins.
Nine-year-old Sophie has collected more than 370 bags of rubbish in a bid to clean up her town.
BBC Radio Cornwall
Cornwall Council has said it is welcoming a campaign that will see a huge digital screen touring the county to highlight areas troubled by littering.
Don't Trash Our Future is an effort to get councils to hand out tougher penalties to people who litter the countryside or do not pick up after their dog.
Councillor Rob Nolan, who leads on the environment, said he recognised Cornwall Council needed to make a bigger effort and said it had already given powers to traffic wardens to penalise those dropping litter.
These volunteers tackle dangerous terrain as they clear plastic from an almost inaccessible beach.
Campaigners say if people pick up litter as they walk their dogs it will make a big difference.