| Postcode district | Post town | Coverage | Local authority area(s) |
| LL11 | WREXHAM | Wrexham, Coedpoeth, Llandegla, Minera, Bradley, Gwersyllt, Rhosrobin, Stansty, Brymbo, Bwlchgwyn, Cymau, Ffrith, Llanfynydd, Gwynfryn, Tanyfron, Brynteg | Denbighshire,[3] Flintshire,[4] Wrexham[5] |
| LL12 | WREXHAM | Wrexham, Caergwrle, Cefn-y-bedd, Cymau, Gresford, Hope, Llay, Marford, Rossett | Flintshire,[6] Wrexham[7] |
| LL13 | WREXHAM | Wrexham, Abenbury, Bowling Bank, Holt, Llan-y-Pwll, Pentre Maelor, Ridley Wood, Bangor-on-Dee, Gyfelia, Marchwiel, Overton, Penley, Worthenbury, Johnstown | Wrexham[8] |
| LL14 | WREXHAM | Wrexham, Rhosllanerchrugog, Cefn Mawr, Ponciau, Rhostyllen, Chirk, Ruabon | Shropshire,[9] Wrexham[10] |
| LL15 | RUTHIN | Ruthin, Bontuchel, Clawddnewydd, Clocaenog, Cyffylliog, Gellifor, Graigfechan, Llanbedr Dyffryn Clwyd, Llanelidan, Llanfair Dyffryn Clwyd, Pwllglas, Rhewl | Denbighshire |
| LL16 | DENBIGH | Denbigh, Bodfari, Llandyrnog, Llanrhaeadr, Bylchau, Groes, Henllan, Llannefydd, Llansannan, Nantglyn, The Green, Trefnant | Conwy,[11] Denbighshire |
| LL17 | ST. ASAPH | St Asaph, Allt Goch, Rhuallt, Tremeirchion, Waen | Conwy,[12] Denbighshire |
| LL18 | RHYL | Rhyl, Bodelwyddan, Cwm Dyserth, Kinmel Bay, Dyserth, Gwaenysgor, Rhuddlan, Trelawnyd | Conwy,[13] Denbighshire, Flintshire[14] |
| LL19 | PRESTATYN | Prestatyn, Gronant | Denbighshire, Flintshire[15] |
| LL20 | LLANGOLLEN | Froncysyllte, Garth, Glyn Ceiriog, Llanarmon Dyffryn Ceiriog, Llwynmawr, Pandy, Pontfadog, Rhewl, Tregeiriog, Trevor, Llangollen, Eglwyseg, Llantysilio | Denbighshire, Wrexham[16] |
| LL21 | CORWEN | Corwen, Cynwyd, Glan-yr-afon, Glasfryn, Llandrillo, Llangwm, Maerdy, Ty Nant, Betws Gwerfil Goch, Bryneglwys, Carrog, Cerrigydrudion, Clawdd Poncen, Derwen, Glyndyfrdwy, Gwyddelwern, Llanfihangel Glyn Myfyr, Llidiart-y-Parc, Melin-y-Wig | Conwy,[17] Denbighshire, Gwynedd[18] |
| LL22 | ABERGELE | Abergele, Towyn, Betws Yn Rhos, Gwytherin, Llanddulas, Llanfairtalhaiarn, Llangernyw, Moelfre, Pandy Tudur, Rhyd-y-Foel, Glascoed, St. George | Denbighshire,[19] Conwy |
| LL23 | BALA | Bala, Llandderfel, Llanfor, Llanuwchllyn, Sarnau | Gwynedd |
| LL24 | BETWS-Y-COED | Betws-y-Coed, Capel Curig, Cwm Penmachno, Penmachno, Pentre Du, Pentrefoelas, Ysbyty Ifan | Conwy |
| LL25 | DOLWYDDELAN | Dolwyddelan | Conwy |
| LL26 | LLANRWST | Llanrwst, Capel Garmon, Nebo, Llanddoged, Melin-y-Coed, Maenan | Conwy |
| LL27 | TREFRIW | Trefriw | Conwy |
| LL28 | COLWYN BAY | Colwyn Bay, Rhos-on-Sea, Eglwysbach, Glan Conwy, Mochdre, Tal-y-Cafn | Conwy |
| LL29 | COLWYN BAY | Colwyn Bay, Llanelian, Llysfaen, Old Colwyn | Conwy |
| LL30 | LLANDUDNO | Llanrhos, Llandudno, Penrhyn Bay | Conwy |
| LL31 | LLANDUDNO JUNCTION | Glanwydden, Llangystennin, Llandudno Junction | Conwy |
| CONWY | Deganwy |
| LL32 | CONWY | Conwy, Dolgarrog, Groesffordd, Henryd, Rowen, Tal-y-Bont, Tyn-y-Groes | Conwy |
| LL33 | LLANFAIRFECHAN | Abergwyngregyn, Llanfairfechan | Conwy, Gwynedd[20] |
| LL34 | PENMAENMAWR | Penmaenmawr, Dwygyfylchi | Conwy |
| LL35 | ABERDYFI / ABERDOVEY | Aberdyfi | Gwynedd |
| LL36 | TYWYN | Tywyn, Abergynolwyn, Bryncrug, Llanegryn, Rhoslefain | Gwynedd |
| LL37 | LLWYNGWRIL | Llwyngwril | Gwynedd |
| LL38 | FAIRBOURNE | Fairbourne, Friog | Gwynedd |
| LL39 | ARTHOG | Arthog | Gwynedd |
| LL40 | DOLGELLAU | Dolgellau, Brithdir, Drws Y Nant, Ganllwyd, Llanelltyd, Llanfachreth, Rhydymain, Tabor | Gwynedd |
| LL41 | BLAENAU FFESTINIOG | Blaenau Ffestiniog, Talwaenydd, Ffestiniog, Gellilydan, Maentwrog, Manod, Trawsfynydd | Gwynedd |
| LL42 | BARMOUTH | Barmouth, Llanaber | Gwynedd |
| LL43 | TALYBONT | Talybont | Gwynedd |
| LL44 | DYFFRYN ARDUDWY | Dyffryn Ardudwy | Gwynedd |
| LL45 | LLANBEDR | Llanbedr | Gwynedd |
| LL46 | HARLECH | Harlech, Llanfair | Gwynedd |
| LL47 | TALSARNAU | Talsarnau, Soar, Ynys | Gwynedd |
| LL48 | PENRHYNDEUDRAETH | Penrhyndeudraeth, Llanfrothen, Minffordd | Gwynedd |
| LL49 | PORTHMADOG | Porthmadog, Borth-y-Gest, Morfa Bychan, Penmorfa, Prenteg, Tremadog | Gwynedd |
| LL51 | GARNDOLBENMAEN | Garndolbenmaen | Gwynedd |
| LL52 | CRICCIETH | Criccieth, Llanystumdwy, Pentrefelin, Rhoslan | Gwynedd |
| LL53 | PWLLHELI | Pwllheli, Efailnewydd, Llannor, Abererch, Chwilog, Llithfaen, Nefyn, Pistyll, Plas Gwyn, Y Ffor, Abersoch, Bwlchtocyn, Llanbedrog, Mynytho, Penrhos, Rhydyclafdy, Aberdaron, Boduan, Botwnnog, Edern, Morfa Nefyn, Sarn, Tudweiliog | Gwynedd |
| LL54 | CAERNARFON | Caernarfon, Clynnogfawr, Llanaelhaearn, Llandwrog, Pontllyfni, Saron, Trefor, Llanllyfni, Aberdesach, Nantlle, Penygroes, Rhyd Ddu, Talysarn, Bontnewydd, Carmel, Dinas, Groeslon, Rhosgadfan, Rhostryfan | Gwynedd |
| LL55 | CAERNARFON | Caernarfon, Bethel (Gwynedd), Bontnewydd, Caeathro, Brynrefail, Clwt-y-Bont, Deiniolen, Penisarwaun, Beddgelert, Ceunant, Cwm-y-glo, Llanberis, Llanrug, Nant Gwynant, Nant Peris, Waunfawr | Gwynedd |
| LL56 | Y FELINHELI | Y Felinheli | Gwynedd |
| LL57 | BANGOR | Bangor, Llanllechid, Rachub, Talybont, Bethesda, Glasinfryn, Llandygai, Mynydd Llandygai, Rhiwlas, Tregarth | Gwynedd |
| LL58 | BEAUMARIS | Beaumaris, Llanddona, Llanfaes, Llangoed, Penmon | Isle of Anglesey |
| LL59 | MENAI BRIDGE | Menai Bridge, Llandegfan, Llansadwrn | Isle of Anglesey |
| LL60 | GAERWEN | Gaerwen, Llanddaniel, Llangaffo, Star | Isle of Anglesey |
| LL61 | LLANFAIRPWLLGWYNGYLL | Llanfairpwllgwyngyll, Brynsiencyn, Dwyran, Newborough, Penmynydd | Isle of Anglesey |
| LL62 | BODORGAN | Bodorgan, Bethel (Anglesey), Hermon, Llangristiolus, Malltraeth, Trefdraeth | Isle of Anglesey |
| LL63 | TY CROES | Ty Croes, Aberffraw, Llanfaelog | Isle of Anglesey |
| LL64 | RHOSNEIGR | Rhosneigr | Isle of Anglesey |
| LL65 | HOLYHEAD | Holyhead, Trearddur Bay, Four Mile Bridge, Rhoscolyn, Bodedern, Bryngwran, Caergeiliog, Llanynghenedl, Trefor, Valley, Gwalchmai, Llanddeusant, Llanfachraeth, Llanfaethlu, Llanfairynghornwy, Llanrhyddlad, Rhydwyn | Isle of Anglesey |
| LL66 | RHOSGOCH | Rhosgoch | Isle of Anglesey |
| LL67 | CEMAES BAY | Cemaes Bay, Tregele | Isle of Anglesey |
| LL68 | AMLWCH | Amlwch, Bull Bay, Carreglefn, Llanfechell, Rhosybol | Isle of Anglesey |
| LL69 | PENYSARN | Penysarn | Isle of Anglesey |
| LL70 | DULAS | Dulas | Isle of Anglesey |
| LL71 | LLANERCHYMEDD | Llanerchymedd | Isle of Anglesey |
| LL72 | MOELFRE | Moelfre | Isle of Anglesey |
| LL73 | MARIANGLAS | Marianglas | Isle of Anglesey |
| LL74 | TYN-Y-GONGL | Tyn-y-Gongl, Benllech | Isle of Anglesey |
| LL75 | PENTRAETH | Pentraeth, Red Wharf Bay, Rhoscefnhir | Isle of Anglesey |
| LL76 | LLANBEDRGOCH | Llanbedrgoch | Isle of Anglesey |
| LL77 | LLANGEFNI | Bodffordd, Rhostrehwfa, Talwrn, Llangefni | Isle of Anglesey |
| LL78 | BRYNTEG | Brynteg | Isle of Anglesey |