January 2021
- 2nd January – Happy Mew Years Day
- 2nd January – National Pet Safety Travel Day (US)
- 14th January – National Dress Up Your Cat Day (US)
- 22nd January – Answer Your Cat’s Question Day
- 24th January – Change a Pet’s Life Day
- Glaucoma Awareness Month
- Thyroid Awareness Month (US)
February 2021
- 4th February – World Cancer Day
- 14th February – Pet Theft Awareness Day
- 18th – 24th February – National Drink Wine With Your Cat Week (US)
- 20th February – National Love Your Pet Day (US)
- 23rd February – World Spay Day
- 28th February – Rare Diseases Day
- Pet Dental Health Month
- National Cat Health Month
- Responsible Pet Owners Month
- National Prevent a Litter Month (US)
- Spay/Neuter Awareness Month
March 2021
- 4th March – World Obesity Day
- 11th March – World Kidney Day
- 19th March – World Sleep Day
- 20th March – World Oral Health Day
- 28th March – Respect Your Cat Day
- 7 – 13th March – Professional Pet Sitter’s Week
- 8th March to 14th March – World Glaucoma Week
- Responsible Pet Owners Month
- National Poison Prevention Week (third week in March)
- Melanoma March (Australia)
April 2021
- 1st April to 7th April – International Pooper Scooper Week
- 4th April – World Stray Animals Day
- 6th April – National Siamese Cat Day (US)
- 7th April – World Health Day
- 11th April – National Pet Day (US)
- 17th April – World Hemophilia Day
- 18th April – Pet Owners Independence Day
- 19th April – World Liver Day
- 19th April – Cat Lady Day
- 25th April – World Veterinary Day
- 25th April – National Pet Parents Day (US)
- 26th April – National Pets and Kids Day (US)
- 30th April – Hairball Awareness Day
- 30th April – National Adopt a Shelter Pet Day (US)
- 30th April – National Tabby Day (US)
- National Pet Month (US)
- Prevention of Cruelty to Animals Month (ASPCA)
- National Heartworm Awareness Month (US)
- National Pet First Aid Awareness Month (US)
- Oral Cancer Awareness Month
May 2021
- 5th May – World Asthma Day
- 2nd – 8th May – Be Kind to Animals Week
- 8th May – National Animal Disaster Preparedness Day
- 12th – 18th May – Food Allergy Awareness Week
- 17th May – World Hypertension Day
- 18th – 24th May – National Volunteer Week (US)
- Thyroid Awareness Month (Australia)
- Chip Your Pet Month
- Arthritis Awareness Month
- National Pet Month (US)
June 2021
- 6th – 12th June –Â Pet Appreciation Week
- 4th June – World Hug Your Cat Day
- 8th June – World Pet Memorial Day
- 13th – 19th June – Animal Rights Awareness Week
- 21st June – Take Your Cat to Work Day
- 21st – 25th June – Take Your Pet to Work Week
- 19th June – National Garfield the Cat Day
- 24th June – Cat World Domination Day
- Adopt a Cat Month
- National Microchipping Month (US)
- Cataract Awareness Month
July 2021
- 5th July – National Pet Remembrance Day (UK)
- 6th July – World Zoonoses Day
- 8th to 13th July – National Diabetes Week (Australia)
- 12th July – National Different Coloured Eyes Day (US)
- 15th July – National Pet Fire Safety Day (US)
- National Lost Pet Prevention Month (US)
- National Pet Hydration Awareness Month (US)
August 2021
- 8th August – World Cat Day
- 15th August – Check the Chip Day
- 17th August – National Black Cat Appreciation Day
- 21st August – International Homeless Animals Day
- 22nd August – National Take Your Cat to the Vet Day
- 28th August – Rainbow Bridge Remembrance Day
- 30th August – National Holistic Pet Day (US)
- National Immunization Awareness Month – (US)
September 2021
- 1st September – Ginger Cat Appreciation Day
- 13th September – National Pet Memorial Day (US)
- 12th – 18th September – Adopt-a-Less-Adoptable-Pet Week
- 21st to 26th September – National Eye Health Week (US)
- 25th September – International Ataxia Awareness Day
- 26th September – World Deaf Day
- 28th September – World Rabies Day
- 29th September – World Heart Day
- 29th September – Beckoning Cat Day
- Pet Sitter Education Month
- National Pet Memorial Month (US)
- Happy Healthy Cat Month
- Animal Pain Awareness Month
October 2021
- 1st October – CATober – Universal birthday of shelter cats
- 4th October – World Animal Day
- 11th – 17th October – National Veterinary Technicians Week (US)
- 16th October – National Feral Cat Day (US)
- 27th October – National Black Cat Day (US)
- 29th October – National Cat Day (US)
- Breast (Mammary Gland) Cancer Awareness Month
- National Pet Wellness Month (US)
- National Animal Safety and Protection Month (US)
November 2021
- First week of November – National Animal Shelter Appreciation Week (US)
- Adopt a Senior Pet Month
- National Senior Pet Month (US)
- Pet Cancer Awareness Month
- Pet Diabetes Month
- 17th November – National Black Cat Day (Italy)
December 2021
- 5th December – International Volunteer Day
- 10th December – International Animal Rights Day
- 15th December – Cat Herders Day
- Cat Lover’s Month