How to Choose a Serger or Overlocker: 21 Factors to Consider (+ Checklist)

I remember when I was looking for a serger years ago, I was completely overwhelmed.

There were so many options. And all those serger features were hard to understand.

I wrote this article to help you choose your serger or overlocker. Learn what features you actually need.

(Ps. a serger and an overlocker are the same machine, just 2 different names).

This guide includes:

• Advice from industry specialists like technicians and serger salespeople.
• Serger features explained simply with pictures and videos.
• A free printable checklist.

You can pin this article to bookmark it for later:

Contents list:

• Let’s figure out your personal serger needs.
• Other things to consider (eyesight issues, how often you sew, and if you sew thick fabrics).
• Serger features explained simply.

Related article: Different types of serger stitches – explained simply for beginners.

Related article: 5 Best Overlockers, According to Industry Experts

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“What overlocker / serger features should I look for?”

Which of these stories sounds most like you?

1. “I only need a basic serger to finish off raw edges. I mostly sew with light to medium weight woven fabrics. I sew occasionally.” (Yes, this is me).

2. “I love experimenting. I sew with wovens, stretchy knits and thick fabrics. I want more than the basic overlock stitch. I want athletic flatlock stitches on my sportswear. I want rolled hems on my chiffon dresses. I sew regularly.” (Yes, this is me).

3. “I want the easiest to use serger on the market. I struggle with threading and choosing the right tension settings. I sew regularly.” (Yes, this is me).

“I only need a basic serger”

If you picked number 1, you probably suit a budget model.

You just need the main overlock stitch. You don’t work with tricky fabrics. And you won’t put your serger under pressure with heavy use.

Look for these features:

• 3 and 4 thread stitch ability. This will give you the main overlock stitches.
• Easy to thread. You’ll want color-coded threading diagrams printed on the machine, and an easy to thread lower looper.
• Differential feed to stop fabric stretching out or puckering.
• Retractable cutting knife so you can serge without cutting.
• Adjustable stitch length and width.
• Recommended: a waste bin to catch fabric fibres. Serging is messy!
• Recommended: a free arm for sewing tubes of fabric. You can sew tubes without this, you’ll just have to learn a different technique.

Most modern sergers have these features.

However, many budget models don’t have a waste bin included, and some models don’t have a free arm.

Watch out for older sergers that have a harder to thread lower looper. I highly recommend avoiding these.

Serger / overlocker suggestions:

• The Brother range is my favorite brand for budget overlockers. They have one of the best threading systems I’ve seen (for manually threaded machines) – so important. Here’s my review on the best model to get, and alternatives if it’s unavailable.

Avoid these sergers / overlockers:

• Janome 9300dx, 9200d and 8002dg (my review post). They have an outdated lower looper design that’s much harder to thread.
• Singer machines (my review). I spoke to multiple industry experts, including a technician, and they were all very negative about the build quality of this brand.
• Cheap department store overlockers. A technician told me these are badly made. Think Aldi, Lidl, and John Lewis (for UK shoppers).

“I love experimenting”

If you picked number 2, you probably suit a mid-range or premium serger.

You sew regularly and with some difficult fabrics, so you’ll want to invest in a better-built machine.

You like experimenting, so you’ll want the ability to do 2, 3 and 4 thread stitches, not just 3 and 4 thread stitches.

Look for these features:

• The features mentioned in the “basic” section above, plus:
• 2, 3 and 4 thread stitches. This will let you create more stitches, like the 2 thread overlock, 2 thread mock flatlock, and 2 thread rolled hem.
• More serger feet to create more effects.
• An extension table for when you’re serging big projects. It’s not essential though.
• Better build quality. You’ll need a more durable machine with more motor power. Avoid budget sergers.
• Easy rolled hem conversion, so you can switch from overlocking to rolled hemming quickly.
• Adjustable pressure. Ideally a user-friendly dial with numbers or markings, not a screw.
• High presser foot lift for serging thick fabrics. Ideally 5 – 6mm, but even 4mm will fit a lot underneath.

Serger / overlocker suggestions

• Brother 4234d review
• Janome 6234xl review
• UPDATE: I now have a full review of the best sergers / overlockers after comparing 40+ machines. My pick for the ‘best all-round overlocker’ is the one that will suit your needs.

“I want the easiest serger”

If you picked number 3, you’ll want to look at the premium market.

You’re looking for a serger that threads itself at the push of a button. Maybe you want it to automatically choose the tension settings for you.

The time these features will save you is worth the extra expense.

At this level, it’s safe to assume that all the sergers you look at will be well-built.

Look for these features:

• The features mentioned in the “basic” and “experiment” sections above, plus:
• Looper air threading. This will thread the fiddly loopers for you with the push of a button.
• Built-in needle threader. This will thread the needles for you. It’s really helpful if you have eyesight issues or unsteady hands.
• Automatic tension. This will save you from figuring out the correct tension settings each time you serge.
• Built-in spreader (or 2 thread converter). This makes switching to sewing 2 thread stitches a bit faster. It’s not a dealbreaker if it’s missing though.

Serger / overlocker suggestions:

• Here’s my review on the best overlockers with air threading and another post on the best overlockers with automatic tension.

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Other features to consider:

How often do you sew?

Daily?

If you sew daily, I highly recommend paying attention to build quality. This is how well or poorly the serger has been made.

I learned from technicians that mass-manufactured, cheap sergers are made with:

• More plastic inside.
• Weaker metals.
• Weaker motors, which means less power.
• More “relaxed” quality control during manufacturing. Manufacturers won’t mind if the parts don’t fit together tightly, or if the metals don’t meet a certain standard.

All of these compromises add up to create a poorer quality product.

If you sew daily, you will wear out a budget serger faster than others. I definitely recommend spending a bit extra for a longer-lasting machine.

I learned from a technician that mid-range and premium sergers are “more substantial machines”.

If you want to learn more, I have a separate article on how to spot good quality sergers and overlockers.

Occasionally?

If you only sew on occasion, a budget serger will normally be fine. You won’t be putting it under much pressure.

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Do you sew with thick fabrics like denim and canvas?

If yes, look for:

• High presser foot lift. Ideally 5 – 6mm, but even 4mm will fit a lot underneath.
• Adjustable pressure. Ideally a user-friendly dial with numbers or markings, not a screw.
• More motor power and a better-built machine. Avoid budget sergers.

High presser foot lift

You’ll want a high presser foot lift for serging thick layers.

4mm is high enough to fit 8 layers of mid-weight denim underneath, so that’s probably fine for most people.

But I have seen sergers that can go up to 5 – 6mm for more space.

Adjustable pressure

You’ll need it to create more pressure to feed thick fabric through the machine, and reduce the pressure for very light fabrics.

Most modern sergers have adjustable pressure.

However, many have a screw to let you change the pressure. These are harder to adjust than a simple numbered dial. A screw is unmarked, so it can be tricky getting back to normal pressure.

Better build quality & more power

Serging thick materials puts pressure on the machine.

You’ll want a serger with more motor power and stronger construction so it can handle this.

You’re more likely to find this in a mid-range or premium serger.

I have a separate article about good quality sergers if you want to learn more.

However, all domestic sergers have a limit, even the premium ones.

The limits of domestic sergers

A technician told me that domestic sergers are designed for 3 or 4 layers of fabric.

Going over 4 layers of denim at the seams every now and then is fine, but you wouldn’t want to be sewing long stretches of 4+ layers of denim regularly.

You will wear out any domestic serger with this kind of use.

If you need to do it, look at industrial sergers instead. They are designed for hours of daily use in factories. They have the power, knives, and build-quality to handle it.

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Do you have eyesight issues that make threading hard?

There are 2 areas you’ll need to thread on a serger: the needles and loopers.

If you have eyesight issues, I highly recommend buying a serger with:

• A built-in needle threader. This will save you from trying to poke a thread through the eye of a needle.
• Air-threaded loopers, if you have the budget. This will let you thread the loopers by pressing a button. That’s it!

Needle threaders

Built-in needle threaders are hard to find on budget models. Expect to buy a mid-range serger.

Looper air threading

With the push of a button, you can thread the loopers with a whoosh of air. It literally takes seconds.

This feature is only found on premium sergers.

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Serger and Overlocker Features Explained

Contents list:

1. 2/3/4/5 thread sergers.
2. Adjustable pressure.
3. Adjustable stitch length and width.
4. Air threading.
5. Automatic tension.
6. Differential feed.
7. Easy lower looper design.
8. Easy rolled hem conversion.
9. Easy to thread.
10. Free arm.
11. High presser foot lift.
12. Needle threader.
13. Retractable cutting knife.
14. Spreader (or 2 thread converter).

2/3/4/5 thread sergers:

3/4 thread sergers

Most budget sergers can only do 3 or 4 thread stitches.

For most people, this is all you’ll need.

2/3/4 thread sergers

Mid-range and premium sergers normally let you do 2 thread stitches too.

This gives you more stitch options to play with, like the 2 thread overlock, 2 thread rolled hem, and 2 thread mock flatlock.

You can’t add this feature later, so now is the time to consider it.

5 thread sergers?

There’s some confusion online about 5 thread sergers.

Generally, you can’t buy a domestic 5 thread serger (industrial sergers are a different story).

I have looked at every major manufacturer’s website in the US and UK (Elna, Brother, Janome, Pfaff, Juki, Singer, Bernina, and Husqvarna).

Today it’s just 4 thread sergers on sale, and in the past there were 3 thread sergers.

If you see a “serger” with more than 4 threads, it’s nearly always a combination machine that combines a serger with a coverstitch machine.

Coverstitches are normally used to hem stretch garments. If you want to do this too, you might want to consider a combination machine.

There are lots of comments online from buyers who say they don’t like switching between serging and coverstitching though.

Adjustable pressure:

Adjustable pressure lets you change how hard the presser foot is pushing down on your fabric.

You’ll need it to create more pressure to feed thick fabric through the machine, and reduce the pressure for very light fabric.

Most machines have a dial with 3 levels, and a few have 5 levels for more finetuning.

I would avoid ones where it’s just a screw with no markings.

It’s harder to change the pressure accurately without markings. And tricky to get back to normal pressure.

Adjustable stitch length & width:

You’ll need to adjust the length and width of your stitches based on how loosely woven a fabric is or how thick/thin it is.

Air threading:

Premium sergers thread the loopers using compressed air.

You just insert your thread inside a hole, push a button or pull a handle, and *tada* it’s threaded! This makes threading the loopers very fast and easy.

A side effect of this is that changing thread colors often (to match your project) won’t be scary anymore. There’s no threading to dread!

Automatic tension:

A few premium sergers can choose tension settings for you automatically.

You select the type of stitch you want, the machine senses the thickness of your fabric, and then it chooses the tension settings for you.

Normally it’s a hassle figuring out the correct tension settings for each fabric. So a machine that can do it for you is a massive time saver.

It’s great for the less patient, and those who have experienced a manual serger before and hate figuring out tension settings.

Differential feed:

Today all modern sergers have a differential feed system.

This will let you stretch out or gather fabric as you’re overlocking.

Why would you want to use differential feed?

Fix puckering seams

If you’re experiencing puckering seams, stretching out the fabric slightly will solve this. It will create a flat, smooth seam.

Fix stretched out seams

If your seam is stretched out, you can very slightly gather the material while serging to create a flat seam.

You might have to do this when sewing stretchy knits.

Create gathers

You can quickly gather fabric if you want to create ruffles or a gathered skirt.

Just turn up the differential feed setting to the max.

It’s so much faster than creating gathers on a sewing machine.

Create “lettuce leaf” edge

The serger can stretch the edge of knit fabrics to create this decorative hem.

How does it work?

Changing the differential feed setting lets you make the front and back feed dogs move at different speeds.

Note: feed dogs are the jagged metal bars under the presser foot.

You can make the back feed dog move faster than the front one to stretch the fabric.

You can make the front feed dog move faster than the back one to gather the fabric.

Or you can keep both feed dogs moving at the same speed for normal serging.

Easy lower looper design

Look for an easy to thread lower looper.

It might be labeled something like “easy” or “F.A.S.T” lower looper threading system.

The lower looper is normally hidden inside the machine, so threading it can be very tricky.

If a serger is designed to let the lower looper come out, you’ll be able to thread it in plain sight.

It makes the threading process much easier.

See the video below; the switch pulls out the lower looper.

Easy rolled hem conversion:

In the past you had to change the needle plate before you could switch from overlock stitches to rolled hem stitches.

This was pretty frustrating and made the process longer.

Today you don’t have to change the plate.

Look for features like “instant rolled hems” or “easy rolled hems” for sergers that have this (most do).

Easy to thread:

Look for color-coded threading guides printed on the machine. These will tell you where to place the threads without you going back to your manual every time.

I also recommend picking a modern serger with an easy to thread lower looper. I would not buy a serger without this.

Free arm:

A free arm is a tube-shaped sewing area. It makes sewing tubes of fabric easier.

You slide your sleeve or trouser hem onto the free arm. This turns the fabric for you as you stitch.

Not all sergers have this.

High presser foot lift:

The higher the presser foot lift, the more fabric you can fit underneath for stitching.

This is useful when working with thick fabrics.

The highest height I have seen so far is 5 to 6 mm.

Needle threader:

This will thread the needles for you. No more poking threads through the eye of a needle.

A must-have for those who struggle with their eyesight.

Here’s how it works on the Brother 4234d:

Retractable cutting knife:

This will let you serge without cutting the fabric.

Most modern sergers have this.

Spreader (or 2 thread converter):

Sergers that can make 2 thread stitches come with a “spreader”. This is also known as a “2 thread converter” (Elna) or “subsidiary looper” (Babylock).

This is a device that sits on your upper looper and lets you make 2 thread stitches.

Some premium models have the spreader built-in.

You won’t have to find your spreader and attach it every time you want a 2 thread stitch. You also won’t risk losing it.

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Related posts:

Here’s my roundup of the best overlockers available.

Here’s how overlockers are different to normal sewing machines.

If you’re not sure what stitches an overlocker makes, or when you would actually use certain ones, check out my beginners guide to overlock stitches. There are lots of close-up photos.

I also asked industry experts what makes an overlocker good or bad quality? This is a really eye-opening read. Learn what sacrifices manufacturers make for cheap overlockers.

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Now it’s your turn

I’d like to hear from you 🙂

Do you have any questions about what to look for in a serger?

Maybe you don’t understand a confusing serger term?

Or you have extra tips on what serger features to consider?

Let me know by leaving a comment below.

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Sources

Phone call with a technician at BSK Ltd on 17 Feb. 2020.

Phone calls with salespeople at sewingmachinesales.co.uk, Frank Nutt Sewing Machines Ltd, Gur Enterprise (UK) LTD trading as GUR Sewing Machines, and Lords Sew-Knit Centre on 27 Feb. 2020.

Annette. ‘Sergers’. She’s A Sewing Machine Mechanic blog. [online] Available at: http://shesasewingmachinemechanic.blogspot.com/p/blog-page.html [accessed: 29 Feb. 2020]

BP Sewing Machine Youtube video. (2017). ‘How to blow out Brother Serger 1034 D (Pat K)’. [online] Available at: https://www.youtube.com/watch?v=mMySkXH-1nE [accessed: 02 March 2020]

Brother EU. Brother overlocker 4234d instructional DVD. [online] Available at: https://www.youtube.com/watch?v=UXEPKDtqCec [accessed: 22 March 2020]

janome.com. ‘The AirThread 2000D: Award Winning Machine’. [online] Available at: https://www.janome.com/products/machines/AT2000D/ [accessed: 22 March 2020]

@GutStoff. Instagram. (2018). [online] Accessible at: https://www.instagram.com/p/Blz4UQhDA6i/ [accessed: 6 March 2020]

debenhams.com. ‘Miss Selfridge – Grey Lettuce Edge Mini Dress’. [online] Available at: https://www.debenhams.com/webapp/wcs/stores/servlet/prod_10701_10001_45303+18J06ASTN_-1 [accessed: 22 March 2020]