In most of the world, including many countries in Europe, Mother’s Day is celebrated on the second Sunday in May. Here is the list of all countries ordered by continent and country population:

Europe:

1. Russia: Last Sunday in November
2. Germany: Second Sunday in May
3. United Kingdom: Fourth Sunday of Lent (Mothering Sunday)
4. France: Last Sunday in May (or first Sunday in June if Pentecost occurs on this day)
5. Italy: Second Sunday in May
6. Spain: First Sunday in May
7. Ukraine: Second Sunday in May
8. Poland: May 26th
9. Romania: First Sunday in May
10. Netherlands: Second Sunday in May
11. Belgium: Second Sunday in May (except Antwerp where it is celebrated on August 15th)
12. Greece: Second Sunday in May
13. Czech Republic: Second Sunday in May
14. Portugal: First Sunday in May
15. Sweden: Last Sunday in May
16. Hungary: First Sunday in May
17. Belarus: Second Sunday in May
18. Austria: Second Sunday in May
19. Serbia: Second Sunday in May
20. Switzerland: Second Sunday in May
21. Bulgaria: March 8th (International Women’s Day is observed as Mother’s Day)
22. Denmark: Second Sunday in May
23. Finland: Second Sunday in May
24. Slovakia: Second Sunday in May
25. Norway: Second Sunday in February
26. Ireland: Fourth Sunday of Lent (Mothering Sunday)
27. Croatia: Second Sunday in May
28. Lithuania: First Sunday in May
29. Slovenia: March 25th
30. Latvia: Second Sunday in May
31. Estonia: Second Sunday in May
32. Cyprus: Second Sunday in May
33. Luxembourg: Second Sunday in June
34. Malta: Second Sunday in May
35. Iceland: Second Sunday in May

Asia:

1. China – Second Sunday in May
2. India – Second Sunday in May
3. Indonesia – December 22nd
4. Pakistan – Second Sunday in May
5. Bangladesh – Second Sunday in May
6. Japan – Second Sunday in May
7. Philippines – Second Sunday in May
8. Vietnam – Second Sunday in May
9. Turkey – Second Sunday in May
10. Iran – June 20th (according to the Iranian calendar)
11. Thailand – August 12th (Queen’s Birthday, also celebrated as Mother’s Day)
12. Myanmar – December 22nd
13. South Korea – May 8th (Parents’ Day, which includes honoring mothers)
14. Iraq – March 21st
15. Afghanistan – Second Sunday in May
16. Uzbekistan – March 8th (International Women’s Day)
17. Saudi Arabia – March 21st
18. Malaysia – Second Sunday in May
19. Yemen – March 21st
20. Nepal – Last day of the month of Baisakh (April/May)
21. Sri Lanka – Second Sunday in May
22. Kazakhstan – March 8th (International Women’s Day)
23. Syria – March 21st
24. Cambodia – March 8th (International Women’s Day)
25. Jordan – March 21st

North America:

1. United States: Mother’s Day is celebrated on the second Sunday in May.
2. Mexico: Mother’s Day is celebrated on May 10th in Mexico. It is a significant holiday and widely celebrated across the country.
3. Canada: Mother’s Day is celebrated on the second Sunday in May, the same as in the United States.
4. Guatemala: Mother’s Day is celebrated on May 10th in Guatemala. It is a special day dedicated to honoring mothers.
5. Cuba: Mother’s Day is celebrated on the second Sunday in May, following the tradition of the United States and Canada.
6. Haiti: Mother’s Day is celebrated on the last Sunday in May in Haiti. It is a day to show appreciation for mothers and motherly figures.
7. Dominican Republic: Mother’s Day is celebrated on the last Sunday in May, similar to Haiti.
8. Honduras: Mother’s Day is celebrated on May 10th in Honduras, coinciding with the celebrations in Mexico.
9. El Salvador: Mother’s Day is celebrated on May 10th in El Salvador, sharing the same date as Mexico and Honduras.
10. Costa Rica: Mother’s Day is celebrated on August 15th in Costa Rica. It is a national holiday dedicated to honoring mothers.

South America:

1. Brazil: Second Sunday of May
2. Colombia: Second Sunday of May
3. Argentina: Third Sunday of October
4. Peru: Second Sunday of May
5. Venezuela: Second Sunday of May
6. Chile: Second Sunday of May
7. Ecuador: Second Sunday of May
8. Bolivia: 27th May (anniversary of the Battle of La Coronilla)
9. Paraguay: 15th May (anniversary of the Independence of Paraguay)
10. Uruguay: Second Sunday of May
11. Guyana: Last Sunday in May
12. Suriname: Last Sunday in May

Africa:

1. Nigeria: Mother’s Day is celebrated on the second Sunday in May, similar to the United States and many other countries.
2. Ethiopia: Mother’s Day is celebrated on the last Sunday of May or the first Sunday of June.
3. Egypt: Mother’s Day is celebrated on March 21st, coinciding with the start of spring.
4. South Africa: Mother’s Day is celebrated on the second Sunday in May, like many other countries.
5. Tanzania: Mother’s Day is celebrated on the second Sunday in May.
6. Kenya: Mother’s Day is celebrated on the second Sunday in May.
7. Algeria: Mother’s Day is celebrated on March 8th, which is also recognized as International Women’s Day.
8. Sudan: Mother’s Day is celebrated on March 21st, coinciding with the start of spring.
9. Morocco: Mother’s Day is celebrated on the last Sunday in May.
10. Uganda: Mother’s Day is celebrated on the second Sunday in May.

Pacific:

1. Australia: Mother’s Day is celebrated on the second Sunday of May. (Population: 25.7 million)
2. Papua New Guinea: Mother’s Day is celebrated on the second Sunday of May. (Population: 9 million)
3. New Zealand: Mother’s Day is celebrated on the second Sunday of May. (Population: 4.8 million)
4. Fiji: Mother’s Day is celebrated on the second Sunday of May. (Population: 896,758)
5. Solomon Islands: Mother’s Day is celebrated on the second Sunday of May. (Population: 699,345)
6. Vanuatu: Mother’s Day is celebrated on the second Sunday of May. (Population: 307,145)
7. Samoa: Mother’s Day is celebrated on the second Sunday of May. (Population: 196,129)
8. Guam (United States territory): Mother’s Day is celebrated on the second Sunday of May. (Population: 167,294)
9. Tonga: Mother’s Day is celebrated on the second Sunday of May. (Population: 105,695)
10. Northern Mariana Islands (United States territory): Mother’s Day is celebrated on the second Sunday of May. (Population: 56,938)
11. Palau: Mother’s Day is celebrated on the second Sunday of May. (Population: 18,008)
12. Marshall Islands: Mother’s Day is celebrated on the second Sunday of May. (Population: 59,190)
13. Micronesia (Federated States of): Mother’s Day is celebrated on the second Sunday of May. (Population: 112,640)
14. Kiribati: Mother’s Day is celebrated on the second Sunday of May. (Population: 118,414)
15. Nauru: Mother’s Day is celebrated on the second Sunday of May. (Population: 10,901)
16. Tuvalu: Mother’s Day is celebrated on the second Sunday of May. (Population: 11,646)
17. Cook Islands (New Zealand territory): Mother’s Day is celebrated on the second Sunday of May. (Population: 10,824)
18. Niue (New Zealand territory): Mother’s Day is celebrated on the second Sunday of May. (Population: 1,618)
19. Tokelau (New Zealand territory): Mother’s Day is celebrated on the second Sunday of May. (Population: 1,340)
20. American Samoa (United States territory): Mother’s Day is celebrated on the second Sunday of May. (Population: 55,641)