Assembly member Nick Ramsay is arrested by police after an incident at his home in Raglan, but is subsequently released without charge.[5]
8 January – It is revealed that Plas Glynllifon, a mansion near Caernarfon, purchased in 2016 for conversion to a hotel, is now in the hands of receivers.[6]
9 January – The rape victim in the Ross England case says in an interview with Victoria Derbyshire that the official inquiry into the conduct of former Welsh Secretary Alun Cairns was "a sham".[7]
12 January – Dafydd Iwan's protest song "Yma o Hyd", originally recorded in 1981, reaches the top of the iTunes chart following a campaign by the Welsh independence movement YesCymru.[8]
13 January – The Welsh Government approves the construction of a new bridge across the river Dyfi at Machynlleth, at a cost of £46 million.[9]
14 January – It is revealed that a new rapid diagnosis centre at Neath Port Talbot Hospital has been effective in reducing waiting times and could result in savings of more than £150,000 per 1,000 patients.[10]
5 February – Dyfed-Powys Police announce that they have been successful in using DNA profiling to confirm the ownership of a stolen cow worth £3,000; they are the first police authority in the UK to employ the technique in such circumstances.[12]
13 February – Nick Ramsay, AM confirms that he had been reinstated as a member of the Welsh Conservative Party Group in the Senedd and has dropped his legal challenge against the decision by group leader Paul Davies to suspend him.[15]
20 February – Natural Resources Wales admits that recent tree-felling activities in the Pentre area caused a blocked culvert that resulted in the second round of flooding to hit the local area during the month.[19]
COVID-19 pandemic in Wales: Health Minister Vaughan Gething announces that all non-urgent outpatient appointments and operations will be suspended at hospitals in Wales in a bid to delay the spread of the COVID-19 pandemic.[26]
1 April – COVID-19 pandemic in Wales: Multinational pharmaceutical company Roche denies the existence of a deal to supply Wales with COVID-19 tests after First Minister Mark Drakeford and Health Minister Vaughan Gething blame the collapse of a deal for a shortage of testing kits.[32]
21 April – The Welsh Government cancels the planned independent inquiry into the circumstances surrounding the dismissal of Carl Sargeant from the cabinet of former First Minister Carwyn Jones and agrees to pay legal fees incurred by the Sargeant family.[35]
6 May – The National Assembly for Wales becomes Senedd Cymru – Welsh Parliament; its members become Members of the Senedd (MS) – Aelodau o'r Senedd (AS).[36]
7 May – COVID-19 pandemic in Wales: Tracey Cooper, the chief executive of Public Health Wales, admits to the Senedd's health committee that she did not know about the Welsh Government's goal of carrying out 9000 COVID-19 tests a day.[37]
12 May – The organisers of the National Eisteddfod, which was due to be held in Tregaron in the first week of August, announce an alternative event, the Eisteddfod "AmGen".[39]
26 June – After police are called to further incidents at Ogmore-by-Sea, the First Minister warns that lockdown restrictions will not be eased if people fail to observe rules on travel and social distancing.[46]
2 July – Airbus confirms that 1,435 jobs will be lost at Broughton in Flintshire.[47]
3 July – COVID-19 pandemic in Wales: The Welsh government confirms that travel restrictions resulting from the pandemic will be relaxed from 6 July.[48]
15 July – The Welsh Government agrees to debate Welsh independence for the first time since the Welsh Assembly was created in 1999. The debate is at the request of Plaid Cymru, following poll results that show a high level of approval for the devolved government's handling of the COVID-19 pandemic in Wales.[49]
31 July – HM Coastguard announce the deployment of unmanned aircraft for search and rescue purposes over North Wales during the coming weekend.[50]
10 August – Flash flooding affects Aberystwyth and thunderstorms occur throughout North Wales.[52]
17 August – It is revealed that Wales's only golden eagle living in the wild has been found dead, probably from natural causes.[53]
26 August – A major fire breaks out near Llangennech when a freight train loaded with diesel fuel is derailed on a journey from Milford Haven. No one is seriously injured, but diesel oil spills into the River Loughor. Local residents are evacuated.[54]
7 September – COVID-19 pandemic in Wales: The first local lockdown in Wales is announced, as the county of Caerphilly is placed under restrictions that will last at least a month. It follows the discovery that 98 people have tested positive in a week, giving the county the highest infection rate in Wales.[55]
21 September – Right-wing extremists from all over the UK are blamed by the police and First Minister for blocking the entrance to a former army camp at Penally in Pembrokeshire being used temporarily to house asylum seekers from Iran and Iraq.[56]
30 September – It is confirmed that eight patients have died in an outbreak of COVID-19 at the Royal Glamorgan Hospital, Llantrisant, and that 60 patients have been infected from a source at the hospital. All surgery at the hospital is suspended. Pontypridd MP Alex Davies-Jones and AM Mick Antoniw issue a joint statement expressing their concern.[59]
In the postponed Queen's Birthday Honours 2020, Welsh recipients include Warren Gatland, former Wales rugby head coach, and opera singer Rebecca Evans (CBE), Wales rugby captain Alun Wyn Jones (OBE) and artist Glenys Cour (MBE).[60]
Death of Kaylea Titford - Kaylea Titford, an 16-year-old Welsh girl with spina bifida and hydrocephalus, is found dead in squalid conditions.[61]
10 October – Bangor, Gwynedd, goes into a local lockdown, joining other North Wales counties: Conwy, Denbighshire, Flintshire and Wrexham.[62]
23 October – A 'firebreak' lockdown is imposed by the Welsh government for a 16-day period.[63] Supermarkets and other large stores are prohibited from selling 'non-essential goods', because many smaller retailers are forced to close.[64]
27 October – After a petition is submitted to the Senedd, requesting it remove the ban on selling non-essential goods, the government reviews the policy and issues clarification.[65][66]
17 November – There are calls for an inquiry into the handling of COVID-19 cases in hospitals and care homes after it is revealed that 53 people were discharged from hospital into Welsh care homes within days of testing positive during the early stages of the pandemic.[67]
20 November – The Welsh government announces that the 17-day Wales firebreak lockdown had an impact on coronavirus figures but warns that restrictions might be re-imposed before Christmas if the downturn does not last.[68]
26 November – New COVID restrictions, to come into force on 4 December, are provisionally announced.[69]
20 December – COVID restrictions are amended, and the previously announced relaxation of rules over the Christmas break is rescinded. The Welsh government announces a complete lockdown in Wales with effect from midnight, with a relaxation of only a few hours on Christmas Day.[70]
29 December – Police impose fines on visitors from England who have broken COVID restrictions in order to visit Pen y Fan.[71]