Afghanistan and Czech Republic jointly hold the record of highest score in T20 Internationals.
T20 internationals began in 2005 with Australia - New Zealand match and in the 15 years' time it has become the most popular format all over the world. Over the years many teams broke old records and created new records.
Last year in Dehradun Afghanistan smashed 278 runs against Ireland and in Ilfov County, the Czech Republic scored 278 runs against Turkey which are the highest totals in this format. On the other hand, in the same year, Turkey was bowled out for just 21 runs which is the lowest ever total of this format.
Highest Team Totals in T20I cricket -
278/3 - Afghanistan vs Ireland at Dehradun, 2019
278/4 - the Czech Republic vs Turkey at Ilfov County, 2019
263/3 - Australia vs Sri Lanka at Pallekele, 2016
260/6 - Sri Lanka vs Kenya at Johannesburg, 2007
260/5 - India vs Sri Lanka at Indore, 2017
252/3 - Scotland vs the Netherlands at Dublin, 2019
248/6 - Australia vs England at Southampton, 2013
245/5 - Australia vs New Zealand at Auckland, 2018
245/6 - West Indies vs India at Lauderhill, 2016
244/4 - India vs West Indies at Lauderhill, 2016
Highest Totals for each Test-playing Nation in T20I cricket -
Afghanistan - 278/3 vs Ireland at Dehradun, 2019
Australia - 263/3 vs Sri Lanka at Pallekele, 2016
Bangladesh - 215/5 vs Sri Lanka at Colombo, 2018
England - 241/3 vs New Zealand at Napier, 2019
India - 260/5 vs Sri Lanka at Indore, 2017
Ireland - 225/7 vs Afghanistan at Abu Dhabi, 2013
New Zealand - 243/6 vs Australia at Auckland, 2018 & 243/5 vs West Indies at Mount Maunganui, 2018
Pakistan - 205/3 vs West Indies at Karachi, 2018
South Africa - 241/6 vs England at Centurion, 2009
Sri Lanka - 260/6 vs Kenya at Johannesburg, 2007
West Indies - 245/6 vs India at Lauderhill, 2016
Zimbabwe - 200/2 vs New Zealand at Hamilton, 2012
Lowest Team Totals in T20I cricket -
21 - Turkey vs the Czech Republic at Ilfov County, 2019
28 - Turkey vs Luxembourg at Ilfov County, 2019
32 - Turkey vs Austria at Ilfov County, 2019
39 - the Netherlands vs Sri Lanka at Chattogram, 2014
45 - West Indies vs England at Basseterre, 2019
46 - Botswana vs Namibia at Kampala, 2019
52 - Serbia vs Greece at Corfu, 2019
53 - Germany vs Italy at Utrecht, 2019
53 - Nepal vs Ireland at Belfast, 2015
53 - Turkey vs Romania at Ilfov County, 2019
Lowest Totals for each Test-playing Nation in T20I cricket -
Afghanistan - 72 vs Bangladesh at Dhaka, 2014
Australia - 79 vs England at Southampton, 2005
Bangladesh - 70 vs New Zealand at Kolkata, 2016
England - 80 vs India at Colombo, 2012
India - 74 vs Australia at Melbourne, 2008
Ireland - 68 vs West Indies at Providence, 2010
New Zealand - 60 vs Sri Lanka at Chattogram, 2014
Pakistan - 74 vs Australia at Dubai, 2012
South Africa - 89 vs Australia at Johannesburg, 2020
Sri Lanka - 82 vs India at Visakhapatnam, 2016
West Indies - 45 vs England at Basseterre, 2019
Zimbabwe - 84 vs New Zealand at Providence, 2010