How Long Does A Jack Russell Stay in Heat+ What To Do


I am a female Jack Russell Terrier owner myself, and it is normal to be curious about how long a heat cycle will last with a female Jack Russell Terrier.

I had the same questions and concerns when I first adopted Luna and wanted to know what I could expect with her heat cycle and what I could do, if anything, to help her.

How long does a female Jack Russell stay in heat?

I have now been raising my female Jack Russell Terrier for the past 2+ years, and here is what I can tell you on this topic.

A female Jack Russell Terrier’s heat cycle will typically last up to 21 days. Female Jack Russell Terriers can have up to 2 heat cycles in a given calendar year. These 21 days are when breeding is most likely to occur with a female Jack Russell Terrier.

Now, that is not all that you need to know on this topic.

I have more information I would like to share with you as someone who owns a Jack Russell Terrier that may help you prepare and be more educated about your Jack Russell when they are in heat and what to expect.

Here is how I intend to present that information for you today:



How Long Does A Female Jack Russell Stay in Heat?

We started off this post with a basic answer to the question, and that is the answer you need to understand about a female Jack Russell being in heat.

In fact, female Jack Russell’s in heat is much like any other female dog being in heat.

The heat cycle itself will typically last up to 21 days.

The heat cycle also runs through 4 basic cycles for a female Jack Russell Terrier that looks like the following:


Phase 1- Proestrus

This phase will last 7-10 days.


Phase 2- Estrus

This phase will last 8-10 days


Phase 3- Diestrus

This phase lasts 56-68 days


Phase 4-Anestrus

Phase 4 and the final phase last 60-100 days.

However, keep in mind that these 4 phases are not indicating the entire heat cycle as the heat cycle is only 21 days when your Jack Russell is most likely capable of breeding.

The 4 phases above are most illustrative of any given year for a female Jack Russell who has not been fixed.

Put simply, your female Jack Russell Terrier is always in one of the 4 phases throughout the year. However, the heat cycle which we are most familiar with will still only fall inside of that 21-day window.

I know that it can be somewhat confusing to understand each of the 4 phases.

The most important thing for you to understand is when your Jack Russell is in heat, when they will begin having a heat cycle, and what to do to help them and provide the best care possible.

I want to touch on when you can expect your Jack Russell Terrier to begin having a heat cycle next.


What Age Will A Female Jack Russell Go into Heat?

A Jack Russell Terrier will typically have their first heat cycle between the ages of 6 months old and 9 months old.

Keep in mind that your Jack Russell will likely have that first heat cycle between 6-9 months of age and then will follow that heat cycle with an additional heat cycle somewhere about 6-7 months later.

Again, you need to be prepared for 2 heat cycles per year that will begin when your female Jack Russell Terrier is between 6-9 months of age.

What most of you are likely curious about next is how long you can expect your female Jack Russell to bleed during this heat cycle, which is what I would like to cover next.


How Long Do Jack Russell’s Bleed for In Heat?

When my female Jack Russell had her first heat cycle, I was terrified about the bleeding and scared that it could not only be an issue for her but also be an issue for the furnishings inside of the home.

I know where you are coming from and where the concern sparks from, to say the least.

Here is the good news.

Jack Russell’s typically will only bleed for about 7-10 days during their heat cycle.

This means the other 50% of the heat cycle, you should not be noticing much or any vaginal bleeding with your Jack Russell Terrier.

Clearly, if bleeding persists or you believe it is out of the ordinary compared to this timeline, it is important for you to contact a vet and consider taking your Jack Russell in for an evaluation to ensure no further complications are taking place.


The Behavior of a Jack Russell Terrier During Estrus (In Heat)

A Jack Russell Terrier that is in heat may behave differently than when they are not in heat.

However, all Jack Russell Terriers are different from how they will handle being in heat.

When Luna (my Jack Russell) was in heat, her behavior did change some but nothing overly dramatic.

First, be prepared for them to lick their “area” frequently when they are in heat.

Especially when they are in heat and in that phase where blood is being produced.

My Jack Russell also seemed a bit more on edge during this 21-day heat cycle.

She would get more irritated towards my yellow lab (other dog) and did not have her typical patience, and she was also less hyper than usual.

In summary, I would say if your Jack Russell is getting ready to enter their first heat cycle, then you need to be prepared for them to potentially be more on edge and slightly more reserved and independent then typical.

At least that is how my Jack Russell behaved.

Can you really blame her?

I am sure it is a lot for a young 6-9-month-old Jack Russell Terrier to go through for the first time and subsequent times, and anytime your Jack Russell is in heat, have some compassion and adjust accordingly.


Other Ways for You to Prepare for Your Jack Russell Being in Heat

I wanted to leave you with a few other recommendations that you should implement based on my experiences and what I have noticed when my female Jack Russell has been in heat.

First and foremost, be careful about where you allow your Jack Russell inside of the house during the 7-10 days when they are actively bleeding while in heat.

Some Jack Russell Terriers will bleed more in heat than others. Still, it is definitely possible for the blood to end up on the carpet and other furnishings.

However, you want to combat this is up to you, but it is something to beware of.

Secondly, understand the mood and the overall emotional feel of your Jack Russell while they are in heat.

Like I mentioned previously, a Jack Russell that is in heat may be behaving slightly differently.

They may be more on edge, more fatigued, and potentially even slightly nippy or more aggressive than usual.

When I went through it with my Jack Russell Terrier, it was not a big deal to be completely honest, but it is something you should be aware of.


A Jack Russell in Heat Is Normal, Plan Ahead

If you have a female Jack Russell Terrier, and you have decided not to have them fixed, a heat cycle is something that is going to happen twice per year and something you need to prepare for and accommodate for.

It is perfectly natural and nothing to be overly concerned with but something to always be prepared for.

Always be sure to contact a vet if anything seems off with your Jack Russell during this time and do your best to accommodate your JR during their heat cycle.

Luna and I certainly wish you the best of luck with your Jack Russell Terriers and the journey you have ahead of you.


What Advice Can You Share with The Readers About A Jack Russell Terrier in Heat?

What other advice can you share with the readers about a Jack Russell Terrier is in heat?

What would you do differently, and have you had any different experiences than what I have shared when your Jack Russell was in heat?

Be sure to share those thoughts, stories, and concerns by dropping a comment below.

As always, Luna and I appreciate you stopping by and reading today, and we will see you all next time.

Josh Martin- Founder and Creator of Terrier Owner

Josh Martin is the proud owner of a female Jack Russell Terrier Named Luna. Josh founded TerrierOwner.com to share the stories of owning a Terrier and to help all terrier owners with the struggles, excitement and common questions that come with being a new terrier parent.

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