Wales
The Single Use Carrier Bags Charge (Wales) Regulations 2010 (amended 2011) are in force from 1st October 2011.
These rules require all retailers in Wales to charge a minimum of 5 pence for every single use carrier bag (including paper bags but not large plastic bags or paper bags used for raw food and certain other products) supplied new. Retailers employing fewer than 10 full-time staff do not have to keep records or make reports. County councils and county borough councils administer this charge. The money raised is kept by the retailer and the rules do not specify where the proceeds of the charge should go. The expectation is that the proceeds should be passed on to charities or to good causes in Wales, and in particular to environmental projects.
A voluntary agreement sets out guiding principles on where the net proceeds should go. The Waste (Wales) Measure 2010 gives Welsh Ministers the power to create regulations which would impose duties on retailers on the destination of proceeds from the charge.
The voluntary agreement is here.
Scotland
The legislation is The Single Use Carrier Bags Charge (Scotland) Regulations 2014 (amended 2015). This came into force on 20th October 2014. As with Wales, the charge is 5p per single use carrier bag, and again businesses employing less than 10 full-time staff are exempt from the requirement to keep, retain and supply information about the bags supplied and the monies received as a result of the charge. Also retailers keep the charge, and again the expectation is that these monies should be donated to good causes.
A Carrier Bag Committment document exists for retailers to sign up to. Details are found here.
Northern Ireland
Requirements are set out in the Carrier Bags Act (Northern Ireland) 2014, the Single Use Carrier Bags Act (Northern Ireland) 2011, and The Single Use Carrier Bags Charge Regulations (Northern Ireland) 2013. These came into effect from 8th April 2013.
These rules oblige retailers (as in Wales and Scotland) to charge 5p for every single use carrier bag supplied new. In addition, from 19th January 2015, retailers must add 5p to all carrier bags with a retail price below 20p, regardless of whether they are single use or reusable. This is called the Carrier Bag Levy and In Northern Ireland, the monies raised must be paid to the Department of Environment (DOE). Further information is found here.
England
The Single Use Carrier Bags Charges (England) Order 2015 sets out the rules, and came into force on 5th October 2015.
The obligation to charge for single-use carrier bags applies to retailers with 250 or more employees. Smaller businesses may also charge on a voluntary basis if they wish. The 250 employee threshold applies to the company not the size of the individual retail outlet. Records must be kept and sent to DEFRA. It is expected that all proceeds (after deduction of reasonable costs) should be donated to good causes, along the lines of the way this works in Wales. Further information is found here.