diff --git a/src/FosterCheckout.php b/src/FosterCheckout.php
index e9c560d..6bda93a 100644
--- a/src/FosterCheckout.php
+++ b/src/FosterCheckout.php
@@ -2,11 +2,16 @@
 
 namespace fostercommerce\craftfostercheckout;
 
+use CommerceGuys\Addressing\AddressFormat\AddressField;
 use Craft;
 use craft\base\Model;
 use craft\base\Plugin;
+use craft\events\DefineAddressFieldLabelEvent;
+use craft\events\DefineAddressFieldsEvent;
+use craft\events\DefineAddressSubdivisionsEvent;
 use craft\events\RegisterTemplateRootsEvent;
 use craft\events\RegisterUrlRulesEvent;
+use craft\services\Addresses;
 use craft\web\twig\variables\CraftVariable;
 use craft\web\UrlManager;
 use craft\web\View;
@@ -146,5 +151,164 @@ function (RegisterUrlRulesEvent $event): void {
 				];
 			}
 		);
+
+		// Although a county is not actually required for UK addresses (the postal service ignores it)
+		// it is normal in the UK to write addresses with a county
+		// with that said, UK counties are a minefield so we should not make the field required
+		// but simply provide it as an option with a reasonable list of county names
+
+		// Adds the Administrative area to UK addresses
+		Event::on(
+			Addresses::class,
+			Addresses::EVENT_DEFINE_USED_FIELDS,
+			function (DefineAddressFieldsEvent $event): void {
+				if ($event->countryCode === 'GB') {
+					$event->fields[] = AddressField::ADMINISTRATIVE_AREA;
+				}
+			}
+		);
+
+		// Changes the label of the Administrative area field to "County" for UK addresses
+		Event::on(
+			Addresses::class,
+			Addresses::EVENT_DEFINE_FIELD_LABEL,
+			function (DefineAddressFieldLabelEvent $event): void {
+				if (
+					$event->countryCode === 'GB' &&
+					$event->field === AddressField::ADMINISTRATIVE_AREA
+				) {
+					$event->label = 'County';
+				}
+			}
+		);
+
+		// A 'reasonable' list of UK county names
+		Event::on(
+			Addresses::class,
+			Addresses::EVENT_DEFINE_ADDRESS_SUBDIVISIONS,
+			function (DefineAddressSubdivisionsEvent $event): void {
+				if (count($event->parents) === 1 && $event->parents[0] === 'GB') {
+					$event->subdivisions = [
+						'' => 'N/A',
+						'Aberdeenshire' => 'Aberdeenshire',
+						'Angus' => 'Angus',
+						'Argyll' => 'Argyll',
+						'Avon' => 'Avon',
+						'Ayrshire' => 'Ayrshire',
+						'Banffshire' => 'Banffshire',
+						'Bedfordshire' => 'Bedfordshire',
+						'Berkshire' => 'Berkshire',
+						'Berwickshire' => 'Berwickshire',
+						'Buckinghamshire' => 'Buckinghamshire',
+						'Caithness' => 'Caithness',
+						'Cambridgeshire' => 'Cambridgeshire',
+						'Cheshire' => 'Cheshire',
+						'Clackmannanshire' => 'Clackmannanshire',
+						'Cleveland' => 'Cleveland',
+						'Clwyd' => 'Clwyd',
+						'Cornwall' => 'Cornwall',
+						'County Antrim' => 'County Antrim',
+						'County Armagh' => 'County Armagh',
+						'County Down' => 'County Down',
+						'County Durham' => 'County Durham',
+						'County Fermanagh' => 'County Fermanagh',
+						'County Londonderry' => 'County Londonderry',
+						'County Tyrone' => 'County Tyrone',
+						'Cumbria' => 'Cumbria',
+						'Derbyshire' => 'Derbyshire',
+						'Devon' => 'Devon',
+						'Dorset' => 'Dorset',
+						'Dumfriesshire' => 'Dumfriesshire',
+						'Dunbartonshire' => 'Dunbartonshire',
+						'Dyfed' => 'Dyfed',
+						'East Lothian' => 'East Lothian',
+						'East Sussex' => 'East Sussex',
+						'Essex' => 'Essex',
+						'Fife' => 'Fife',
+						'Gloucestershire' => 'Gloucestershire',
+						'Gwent' => 'Gwent',
+						'Gwynedd' => 'Gwynedd',
+						'Hampshire' => 'Hampshire',
+						'Herefordshire' => 'Herefordshire',
+						'Hertfordshire' => 'Hertfordshire',
+						'Inverness-shire' => 'Inverness-shire',
+						'Isle of Arran' => 'Isle of Arran',
+						'Isle of Barra' => 'Isle of Barra',
+						'Isle of Benbecula' => 'Isle of Benbecula',
+						'Isle of Bute' => 'Isle of Bute',
+						'Isle of Canna' => 'Isle of Canna',
+						'Isle of Coll' => 'Isle of Coll',
+						'Isle of Colonsay' => 'Isle of Colonsay',
+						'Isle of Cumbrae' => 'Isle of Cumbrae',
+						'Isle of Eigg' => 'Isle of Eigg',
+						'Isle of Gigha' => 'Isle of Gigha',
+						'Isle of Harris' => 'Isle of Harris',
+						'Isle of Iona' => 'Isle of Iona',
+						'Isle of Islay' => 'Isle of Islay',
+						'Isle of Jura' => 'Isle of Jura',
+						'Isle of Lewis' => 'Isle of Lewis',
+						'Isle of Mull' => 'Isle of Mull',
+						'Isle of North Uist' => 'Isle of North Uist',
+						'Isle of Rhum' => 'Isle of Rhum',
+						'Isle of Scalpay' => 'Isle of Scalpay',
+						'Isle of Skye' => 'Isle of Skye',
+						'Isle of South Uist' => 'Isle of South Uist',
+						'Isle of Tiree' => 'Isle of Tiree',
+						'Isle of Wight' => 'Isle of Wight',
+						'Kent' => 'Kent',
+						'Kincardineshire' => 'Kincardineshire',
+						'Kinross-shire' => 'Kinross-shire',
+						'Kirkcudbrightshire' => 'Kirkcudbrightshire',
+						'Lanarkshire' => 'Lanarkshire',
+						'Lancashire' => 'Lancashire',
+						'Leicestershire' => 'Leicestershire',
+						'Lincolnshire' => 'Lincolnshire',
+						'London' => 'London',
+						'Merseyside' => 'Merseyside',
+						'Mid Glamorgan' => 'Mid Glamorgan',
+						'Middlesex' => 'Middlesex',
+						'Midlothian' => 'Midlothian',
+						'Morayshire' => 'Morayshire',
+						'Nairnshire' => 'Nairnshire',
+						'Norfolk' => 'Norfolk',
+						'North Humberside' => 'North Humberside',
+						'North Yorkshire' => 'North Yorkshire',
+						'Northamptonshire' => 'Northamptonshire',
+						'Northumberland' => 'Northumberland',
+						'Nottinghamshire' => 'Nottinghamshire',
+						'Orkney' => 'Orkney',
+						'Oxfordshire' => 'Oxfordshire',
+						'Peeblesshire' => 'Peeblesshire',
+						'Perthshire' => 'Perthshire',
+						'Powys' => 'Powys',
+						'Renfrewshire' => 'Renfrewshire',
+						'Ross-shire' => 'Ross-shire',
+						'Roxburghshire' => 'Roxburghshire',
+						'Selkirkshire' => 'Selkirkshire',
+						'Shetland' => 'Shetland',
+						'Shropshire' => 'Shropshire',
+						'Somerset' => 'Somerset',
+						'South Glamorgan' => 'South Glamorgan',
+						'South Humberside' => 'South Humberside',
+						'South Yorkshire' => 'South Yorkshire',
+						'Staffordshire' => 'Staffordshire',
+						'Stirlingshire' => 'Stirlingshire',
+						'Suffolk' => 'Suffolk',
+						'Surrey' => 'Surrey',
+						'Sutherland' => 'Sutherland',
+						'Tyne and Wear' => 'Tyne and Wear',
+						'Warwickshire' => 'Warwickshire',
+						'West Glamorgan' => 'West Glamorgan',
+						'West Lothian' => 'West Lothian',
+						'West Midlands' => 'West Midlands',
+						'West Sussex' => 'West Sussex',
+						'West Yorkshire' => 'West Yorkshire',
+						'Wigtownshire' => 'Wigtownshire',
+						'Wiltshire' => 'Wiltshire',
+						'Worcestershire' => 'Worcestershire',
+					];
+				}
+			}
+		);
 	}
 }