How to Choose Insoles for Plantar Fasciitis and Flat Feet

What Are the Best Insoles for Flat Feet and Plantar Fasciitis?

The best insoles for flat feet and plantar fasciitis are generally those that combine appropriate arch support, heel stability, pressure distribution and sufficient cushioning, while fitting correctly inside your shoes.

However, “best” does not necessarily mean the firmest or most supportive insole.

A person with flexible flat feet and plantar heel pain may respond differently from someone with a high degree of pronation, a very sensitive arch, significant foot deformity or another underlying condition.

When choosing an insole, consider:

• Your type of flat foot

• Where your foot hurts

• How much arch support you tolerate

• Insole firmness

• Heel cup or heel stability

• Cushioning

• Insole thickness

• Shoe compatibility

• Your daily activity

• Whether the insole can be adjusted or trimmed

• Whether you need professional assessment

For a broader explanation of flat feet and arch support, see How to Choose Insoles for Flat Feet.

Why Do Flat Feet and Plantar Fasciitis Often Get Discussed Together?

Flat feet and plantar fasciitis are different conditions, but they can occur together.

Flat feet generally describe a foot with a lower or flattened medial longitudinal arch, particularly when weight-bearing.

Plantar fasciitis involves irritation and pain associated with the plantar fascia, a strong band of connective tissue running along the underside of the foot.

Foot structure and mechanics can influence how forces are distributed through the foot during standing and walking. However, having flat feet does not automatically mean you will develop plantar fasciitis.

Plantar fasciitis is multifactorial. Activity level, footwear, calf and ankle flexibility, body weight, training changes and foot mechanics can all be relevant.

If you want to understand the condition itself, read What Does Arch Support Do? Benefits, Uses & Who Needs It and Does Arch Support Help Plantar Fasciitis?.

How Do I Choose Insoles for Plantar Fasciitis and Flat Feet?

A practical way to choose insoles for plantar fasciitis and flat feet is to assess six factors:

1. Arch support

2. Firmness

3. Heel support and cushioning

4. Fit and size

5. Shoe compatibility

6. Your symptoms and activity

Let's look at each one.

1. Choose the Right Amount of Arch Support

Arch support is one of the most important features to consider when choosing insoles for flat feet and plantar fasciitis.

But more arch support is not necessarily better.

An insole should contact and support the arch without creating excessive pressure or feeling as though it is pushing aggressively into the foot.

What should arch support feel like?

Ideally, the support should feel:

• Stable

• Supportive

• Comfortable

• Secure inside the shoe

• Neither painfully high nor excessively intrusive

Some people initially notice the insole under the arch. That does not automatically mean the insole is wrong.

However, persistent or increasing pain, numbness, tingling, pressure points or significant discomfort are reasons to reassess the fit and design.

For more detail on this distinction, see Can the Wrong Arch Support Make Plantar Fasciitis Worse?.

Should flat feet use arch support?

Not every person with flat feet needs an insole.

Some people have asymptomatic flat feet and do not require correction or support.

For people who have symptoms, an appropriately designed insole may be considered as one component of conservative management.

Research on adults with flat feet is mixed. A 2021 systematic review concluded that evidence for foot orthoses in adult flatfoot was limited and inconsistent, while a later systematic review and meta-analysis found that orthoses may reduce pain in adults with flexible flat feet, although heterogeneity between studies limits certainty.

This is why the objective should be appropriate support, rather than trying to force every flat foot into the same position.

2. Consider Insole Firmness

Firmness is another important factor when choosing an insole for flat feet and plantar fasciitis.

Insoles can broadly range from:

• Soft and cushioned

• Semi-rigid

• Firm or rigid

• Multi-layer designs combining different materials

Are firm insoles better for flat feet?

Not necessarily.

A firmer insole can provide a stronger structural interface with the foot, but an overly rigid or poorly matched design may feel uncomfortable.

A softer insole can improve cushioning and comfort but may not provide the same level of structural support.

For many people, a semi-rigid or structured design with some cushioning can be a practical middle ground.

The right choice depends on your foot, symptoms and footwear.

3. Look for Heel Support as Well as Arch Support

Plantar fasciitis commonly causes pain around the heel or underside of the foot, so heel design deserves attention.

A suitable insole may include features such as:

• A contoured heel cup

• Heel cushioning

• Shock-absorbing materials

• A stable heel platform

• A combination of heel and arch support

This does not mean that a heel cushion alone is always the best solution.

A heel cushion primarily addresses cushioning around the heel, while an arch-support insole is designed to interact with the foot's arch and overall support structure.

If you're deciding between the two specifically for plantar fasciitis, see Arch Support vs Heel Cushion for Plantar Fasciitis.

4. Check the Insole's Fit

Even a well-designed insole may not work well if it does not fit your foot or shoe correctly.

Check:

• Length

• Width

• Heel position

• Arch position

• Toe-room

• Overall thickness

• Whether the insole moves inside the shoe

An insole should not force your toes into a cramped position.

If the insole makes the shoe too tight, it can create new pressure points and reduce comfort.

Should you remove the original shoe insole?

If your footwear has a removable factory insole, removing it may create more room for a replacement insole.

However, this depends on the shoe and the replacement insole.

Some shoes are designed around their original footbed, so changing it can alter the fit.

Always check the manufacturer's instructions and make sure your heel remains securely positioned inside the shoe.

5. Choose an Insole That Works With Your Shoes

An excellent insole in the wrong shoe may still be a poor solution.

Before buying, consider whether you intend to use the insole in:

• Walking shoes

• Running shoes

• Work shoes

• Casual shoes

• Boots

• Sports footwear

• Everyday sneakers

A thick insole may not work well inside a low-volume shoe.

Similarly, a rigid insole may require more space than a thin everyday insert.

Some products are trim-to-fit, which can make fitting easier.

For example, Frido's Plantar Fasciitis Pain Relief Ortho Insoles are listed with a trim-to-fit design and combine arch support, a deep heel cup and cushioning. These are product features, not a guarantee that the product is appropriate for every individual.

6. Consider How You Use Your Feet Every Day

Your daily activity should influence your insole choice.

Someone who:

• Sits at a desk most of the day

• Walks several kilometres daily

• Stands for eight hours

• Runs regularly

• Works on hard floors

• Goes to the gym

may have different requirements.

Insoles for standing all day

If you spend long periods standing, comfort, pressure distribution and shoe fit become especially important.

Insoles for walking

If walking is your primary activity, consider an insole that balances support and comfort without taking excessive space inside the shoe.

Insoles for running

Running introduces substantially greater repetitive loading than ordinary walking.

If you run with flat feet and plantar fasciitis, the appropriate choice may depend on your symptoms, training volume, footwear and individual mechanics.

What Features Should You Look for in Insoles for Plantar Fasciitis and Flat Feet?

If you have both conditions, look beyond the word “orthopedic” on the packaging.

Consider these features:

No single feature guarantees pain relief.

The combination needs to work for your feet and footwear.

Should I Choose Firm or Soft Insoles for Flat Feet?

This is one of the most common questions people ask when choosing insoles for flat feet and plantar fasciitis.

Soft insoles

Soft insoles can prioritize:

• Cushioning

• Comfort

• Shock absorption

• Pressure reduction

They may be attractive if your primary complaint is general foot fatigue or sensitivity.

However, a very soft material does not automatically provide meaningful arch support.

Firm or semi-rigid insoles

These can prioritize:

• Structural support

• Arch contact

• Foot stability

• A more defined platform

But very firm support can be uncomfortable if the arch profile or geometry does not match your foot.

What is the practical choice?

For someone with both flat feet and plantar fasciitis, a structured insole with appropriately placed arch support plus some cushioning may be worth considering.

The important word is appropriately.

More firmness is not automatically better.

Are Arch Support Insoles Good for Flat Feet and Plantar Fasciitis?

They can be useful for some people, particularly when symptoms are associated with foot mechanics or prolonged loading, but they are not universally necessary.

Research provides some support for orthoses as a pain-management option, but the evidence is not strong enough to say that everyone with flat feet or plantar fasciitis should wear them.

A 2026 systematic review and meta-analysis of eight randomized controlled trials involving 391 people with plantar fasciitis found that foot orthoses significantly reduced pain compared with controls, but did not produce significant improvements in foot function or walking ability. The authors described orthoses as an adjunct rather than a standalone treatment.

For flat feet, a 2024 systematic review and meta-analysis found that foot orthoses influenced several measures of lower-limb mechanics during walking in adults with flexible flat feet, including rearfoot eversion and selected ankle and knee moments.

This supports a more nuanced conclusion:

Arch-support insoles can change foot mechanics and may help symptoms in some people, but they should not be viewed as a universal cure for flat feet or plantar fasciitis.

How Much Arch Support Do You Need?

There is no universal arch-support height that is correct for every person.

The required support depends on factors such as:

• Arch shape

• Foot flexibility

• Symptoms

• Pronation pattern

• Insole geometry

• Shoe design

• Activity

• Individual tolerance

If you are unsure what type of arch you have, start with How to Tell What Type of Foot Arch You Have.

You can also read How to Measure Your Foot Arch at Home.

Important: Don't choose an insole solely from a wet-foot test

A wet-foot test can provide a rough visual indication of arch contact, but it is not a complete clinical assessment.

If your symptoms are persistent, severe or unusual, a healthcare professional can assess your foot structure and movement more comprehensively.

Can Insoles Help Flat Feet and Plantar Fasciitis?

They may help with symptoms, but they do not necessarily change the underlying structure of adult flat feet or permanently “cure” plantar fasciitis.

For plantar heel pain, a 2018 systematic review and meta-analysis of 19 trials involving 1,660 participants found moderate-quality evidence that foot orthoses reduced pain in the medium term, although the clinical importance of the difference was uncertain. It also found no clear difference between customized and prefabricated orthoses.

Another systematic review found no clear superiority of orthoses over sham or other conservative treatments for plantar heel pain, illustrating why evidence on this subject should not be oversimplified.

For that reason, it is better to think of insoles as one possible component of symptom management, rather than a guaranteed solution.

Should Insoles for Flat Feet Have a Heel Cup?

A heel cup can be useful when heel stability or cushioning is an important consideration.

A deeper or more contoured heel area may help position the heel within the shoe and provide a more stable interface.

However, a heel cup should not automatically be considered a replacement for an appropriately selected arch-support insole.

The choice depends on your symptoms.

If your main issue is:

Arch discomfort or a feeling of inadequate support:
An appropriately designed arch-support insole may be more relevant.

Heel cushioning sensitivity:
A heel cushion or heel-support feature may be more relevant.

Flat feet plus plantar heel pain:
A combination of arch support, heel stability and cushioning may be worth considering.

For the distinction between these options, read Arch Support vs Heel Cushion for Plantar Fasciitis.

Full-Length vs 3/4-Length Insoles

The length of an insole can affect both comfort and shoe compatibility.

Full-length insoles

These extend from the heel toward the toes and can provide support across more of the foot.

They are often useful when you are replacing the shoe's existing footbed.

3/4-length insoles

These stop before the toes and can be useful when:

• Shoe space is limited

• Toe-box space is important

• The original forefoot area needs to remain unobstructed

Neither format is automatically better for plantar fasciitis and flat feet.

The most important considerations remain support, fit, comfort and compatibility with your footwear.

OTC Insoles vs Custom Orthotics for Flat Feet and Plantar Fasciitis

Another common question is whether you need custom orthotics.

Over-the-counter insoles

OTC insoles are:

• More accessible

• Generally less expensive

• Available in different support profiles

• Easy to try

• Suitable for many everyday situations

Custom orthotics

Custom orthotics are made or prescribed based on an individual's assessment and may be appropriate in selected cases.

However, custom does not automatically mean better for everyone.

The evidence does not consistently demonstrate that custom orthoses are superior to prefabricated options for plantar heel pain. The 2018 systematic review found no difference between customized and prefabricated orthoses at the assessed time points.

Can OTC Insoles Be Enough for Flat Feet and Plantar Fasciitis?

For some people, yes.

An OTC insole may be a reasonable first option when:

• Symptoms are mild to moderate

• There is no major foot deformity

• The foot is reasonably comfortable with the selected support

• The insole fits correctly

• There are no concerning symptoms

However, persistent pain or significant functional problems warrant professional assessment rather than repeatedly buying different insoles.

How Do You Know If an Insole Is Working?

An insole should be judged by how your symptoms and function respond, not simply by how much arch support you can feel.

Potential signs of a good fit include:

• Comfortable arch contact

• Stable heel position

• No sharp pressure points

• No numbness or tingling

• No persistent increase in pain

• Comfortable walking

• Adequate room for the toes

• The shoe still fits properly

An insole does not have to feel completely invisible to be effective.

At the same time, pain is not something you should simply push through because the product is supposed to provide support.

Can the Wrong Insole Make Plantar Fasciitis Worse?

It can.

An insole may be unsuitable if:

• The arch is too high

• The support is too aggressive

• The heel position feels unstable

• The insole is too thick

• The shoe becomes too tight

• The support is positioned incorrectly

• The insole does not match your foot shape

If your symptoms consistently worsen after using a new insole, reassess the fit rather than assuming you simply need to “break it in.”

Read Can the Wrong Arch Support Make Plantar Fasciitis Worse? for a dedicated discussion.

How Long Does It Take to Get Used to New Insoles?

Some people adapt quickly, while others need more time.

If the insole feels unfamiliar but is not causing significant discomfort, gradual use can be a practical approach.

For example:

1. Wear the new insole for a short period initially.

2. Remove it if significant discomfort develops.

3. Increase wear time gradually as tolerated.

4. Monitor your symptoms during walking and standing.

5. Reassess the fit if discomfort persists.

Do not assume that severe pain is a normal part of the adjustment process.

A Simple Checklist: How to Choose Insoles for Flat Feet and Plantar Fasciitis

Before purchasing an insole, ask:

About your feet

• Do I actually have flat feet?

• Are my arches flexible or relatively rigid?

• Where exactly does my foot hurt?

• Is my pain mainly in the heel, arch or elsewhere?

About the insole

• Does it provide appropriate arch support?

• Is the support too high or too low?

• Is it soft, semi-rigid or rigid?

• Does it have adequate heel support?

• Does it provide cushioning where I need it?

• Is the size correct?

About your footwear

• Is the original insole removable?

• Will the replacement make the shoe too tight?

• Does my heel remain secure?

• Do I still have adequate toe room?

• Is the insole suitable for the activity?

About your symptoms

• Does it feel comfortable?

• Does walking feel stable?

• Is pain improving, unchanged or increasing?

• Am I developing new pressure points?

• Am I experiencing numbness or tingling?

This checklist is often more useful than simply searching for the “best insoles for plantar fasciitis and flat feet.”

Which Frido Insoles Can You Consider?

Frido currently offers several insole designs aimed at different needs, including products categorized for flat feet and plantar-fasciitis/pain relief. Its insole collection includes rigid and semi-rigid arch-support options as well as plantar-fasciitis-focused designs.

For flat-foot-focused support

The Frido Arch Support Insoles are positioned as a semi-rigid arch-support option for flat feet. Frido describes the design as providing adaptive arch support rather than using a fully rigid structure.

For plantar fasciitis + heel support

The Frido Plantar Fasciitis Pain Relief Ortho Insoles combine arch support, a deep heel cup and cushioning and are specifically marketed for plantar fasciitis, heel pain, flat feet and overpronation.

For broader insole options

You can compare different designs in Frido's Insoles collection, including products categorized for flat feet, pain relief, sports and everyday comfort.

Important: Product features describe how a product is designed; they do not mean that a particular insole will be appropriate for every person or guarantee pain relief.

When Should You See a Doctor or Podiatrist?

Insoles are not a substitute for professional assessment when symptoms are persistent or severe.

Consider seeking medical or podiatric advice if:

• Pain is severe

• Pain started suddenly after an injury

• You cannot walk normally

• Symptoms continue despite reasonable self-care

• You have significant swelling

• You experience numbness or tingling

• You have weakness

• Pain is progressively getting worse

• You have a significant change in foot shape

• One foot has suddenly become much flatter than the other

People with diabetes, neurological conditions, circulation problems or other medical conditions affecting the feet should also take persistent foot symptoms seriously.

Can Flat Feet Be the Reason for Your Plantar Fasciitis?

Flat feet may be one contributing factor, but they are not necessarily the sole cause.

Plantar fasciitis has multiple potential contributing factors, and foot structure is only one part of the picture.

This is why simply buying a high-arch insole and attempting to “correct” flat feet may not address the complete problem.

A better approach is:

Understand your foot → understand your symptoms → choose appropriate support → ensure proper fit → introduce it gradually → monitor your response.

The Bottom Line: Choosing Insoles for Plantar Fasciitis and Flat Feet

If you have both flat feet and plantar fasciitis, don't choose an insole simply because it has the highest arch, the firmest material or the most cushioning.

Instead, look for an insole that provides:

• Appropriate arch support

• Comfortable pressure distribution

• Suitable firmness

• Adequate heel stability

• Useful cushioning

• Correct sizing

• Good shoe compatibility

• Comfort during gradual use

Evidence suggests foot orthoses can reduce pain in some people with plantar fasciitis and can influence aspects of lower-limb mechanics in adults with flexible flat feet. However, the evidence is not strong enough to claim that every person with flat feet or plantar fasciitis needs an insole.

The goal should therefore be the right support for your individual feet-not maximum support.