Hartz UltraGuard Plus Flea & Tick Collar for Dogs, Medium & Large Breeds, 1 Collar (7-mos. supply)

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About This Item

Details

  • Provides full body protection from fleas and ticks for up to 7 months and can kill and even prevent flea eggs for up to 7 months—stopping the flea life cycle to help prevent reinfestation.
  • Specially designed for large dogs and can be adjusted to fit necks up to 22 inches.
  • Water resistant collar continues to fight fleas when wet and allows your dog to play in the rain, take a bath and even go for a swim without removing.
  • Kills through contact—eliminates fleas and ticks.
  • Proudly made in the USA.

Ingredients

Instructions

Size

FAQ

Important Information

Fleas rise to the top of your pet's coat as they die, so consider it a triumph if you start seeing more fleas at first, after treating your pet. If you’re still seeing fleas after application, it may be because your pet has picked up new fleas from the environment, which may include other pets, surfaces and outdoor areas. It may take up to 30 days to break the entire flea life cycle. Additionally, you should also treat sources of new fleas (i.e., carpet, yard, etc.) to ensure complete flea control.

About Hartz Ultraguard Dog Collars

Why Choose a Hartz Flea & Tick Collar?

Hartz Flea & Tick Collars provide convenient, mess-free flea and tick protection. Easy to put on and adjust for comfort, they can be worn alongside your dog’s regular collar.

How Hartz Flea & Tick Collars Work

Hartz Flea & Tick Dog Collars contain active ingredients that are slowly released and distributed over your dog’s body. These active ingredients kill and repel fleas and ticks to keep your pup pest-free and happy.

Long-Lasting Flea & Tick Protection

Pest Protection

Hartz UltraGuard dog collars kill and repel fleas and ticks and can be worn with your dog’s regular collar.

Full Body Protection

The active ingredients spread across your dog’s skin, providing continuous, full-body coverage for up to 6 months.

Water Resistant

UltraGuard collars are water-resistant, so they won’t lose their effectiveness if your pup takes a stroll in the rain.

Don’t Settle for Stiff

Hartz UltraGuard collars are soft and flexible to provide comfortable flea and tick protection.

About Hartz

For more than 95 years, Hartz has been dedicated to creating products that show pets the same unconditional love they give us. Hartz is a leader in quality, innovative products for dogs and cats, including Oinkies, Delectables, UltraGuard, Nature’s Shield, Home Protection, Comfitables, and Groomer's Best brands. Through the Hartz Loving Paws shelter outreach program, Hartz is committed to helping animal welfare organizations that protect and care for pets until they find their forever homes.

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Questions & Answers

6 Customer Questions

How long does this need to be worn?

Answer by Chewy • Mar 07, 2022
This collar provides full body protection from fleas and ticks for up to 7 months.

What specific types of ticks does the collar protect from?

Answer by Chewy • Aug 03, 2021
The UltraGuard Plus Flea & Tick Collar for Dogs will protect from Brown Dog and Deer ticks only.

I have Minnie poodles 13 pounds will it work

Answer by Chewy • May 29, 2022
This flea and tick collar is suitable for Medium and Large breed dogs only. It fits dogs with necks that measure up to 22 inches. We recommend the Hartz UltraGuard Plus Dog Flea & Tick Collar for Dogs, X-Small & Toy & Small Breeds available on our site.

is it waterproof

Answer by Chewy • May 13, 2022
This collar is water-resistant. Wetting the collar will not impair its effectiveness or the pet's protection. If the pet goes swimming or is out in the rain, it is not necessary to remove the collar.
Reviews
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4.1
Rated 4.1 out of 5 stars
489 Ratings
Terms & Conditions

Customers Mention

Chewy identifies key considerations with the help of artificial intelligence and our veterinarians.

Active Ingredients

58% Positive

Comfort and Fit

62% Positive

Duration of Protection

52% Positive

Effectiveness

58% Positive

140 Customer Reviews

Always consult a veterinarian about your pet’s health needs. Customer reviews should not be used as medical advice.

Rated 5 out of 5 stars
By Brianna on Dec 9, 2025

Great for camping!

My dog is on oral flea and tick prevention, but I get one of these collars each year for a handful of camping trips. They don’t seem to bother him and they last

My dog is on oral flea and tick prevention, but I get one of these collars each year for a handful of camping trips. They don’t seem to bother him and they last all season when kept in a ziploc bag between use. Ive never found a critter on him after using, could be coincidence or these could work that well

Rated 4 out of 5 stars
By sharon on Nov 24, 2025

cost

so far so good, had to get something new, cause the other stuff for fleas is no longer getting made, so this is cheaper , so I save money yea!

so far so good, had to get something new, cause the other stuff for fleas is no longer getting made, so this is cheaper , so I save money yea!

Rated 4 out of 5 stars
By Priscilla on Sep 22, 2025

These flea collars work great!

These collars work great. And they do last up to 7 months. My cat and dog started getting fleas about 7 months after I got these collars. So I bought some more,

These collars work great. And they do last up to 7 months. My cat and dog started getting fleas about 7 months after I got these collars. So I bought some more, bathed them both, put on their new collars and they don't scratch and chew anymore!

Rated 1 out of 5 stars
By Cameron on Oct 19, 2025

This brand suck

It doesn't actually do anything I use expensive flea collars before and I thought this was going to be good but don't waste your time with this brand

It doesn't actually do anything I use expensive flea collars before and I thought this was going to be good but don't waste your time with this brand

Rated 5 out of 5 stars
By Ann on Jul 30, 2025

Hart Flea Collar

Great product. The first time my dog wore it was last summer because he had a very bad flea infestation. He was losing a lot of fur and nothing we used was helping

Great product. The first time my dog wore it was last summer because he had a very bad flea infestation. He was losing a lot of fur and nothing we used was helping much. I tried Hartz and notice after a few weeks that my dog wasn't itching as much and all of the fur he lost eventually grew back. He wore the collar through the fall and spring, so this summer I stocked up on Hartz again. Now my little guy is happy again.

Rated 2 out of 5 stars
By erandy on Oct 10, 2025

Terrible skin reaction

My mini golden doodle had a terrible skin reaction. It did nothing for the fleas and her skin broke out in rashes and hot spots had to cut it off

My mini golden doodle had a terrible skin reaction. It did nothing for the fleas and her skin broke out in rashes and hot spots had to cut it off

Rated 5 out of 5 stars
By Idie on Aug 7, 2025

Works just fine

Two years and no fleas, ticks, or side affects from the collar. Also love Chewy, the business, and wish all businesses were as customer oriented and just plain

Two years and no fleas, ticks, or side affects from the collar. Also love Chewy, the business, and wish all businesses were as customer oriented and just plain kind and professional. I’ve never had a bad experience with Chewy as they are very accommodating to their clients! Bravo Chewy!!

Rated 5 out of 5 stars
By Peggy on Jul 22, 2025

Flea and Tick prevention

Hartz is a well known and respected company that has been around for many years. I've used their collars on my dogs for many years and they have kept them save from

Hartz is a well known and respected company that has been around for many years. I've used their collars on my dogs for many years and they have kept them save from fleas and ticks. The less medication I have to put into my dogs, the happier I am.

Rated 2 out of 5 stars
By miranda on Nov 6, 2025

Worked for one dog

Worked great for Yoko. Unfortunately Elvis broke out in hives.

Worked great for Yoko. Unfortunately Elvis broke out in hives.

Rated 1 out of 5 stars
By Peggy on Jun 15, 2025

Not happy

I washed them in veternarian shampoo, dried them off reall good, stretched them as directed. They worked for half a day and then there were fleas. I made sure to

I washed them in veternarian shampoo, dried them off reall good, stretched them as directed. They worked for half a day and then there were fleas. I made sure to spray the house, furniture, their beds, nothing is working