Bobbin thread showing on top of embroidery: how to fix it

Bobbin thread shows on top when the upper thread pulls too tight against the bobbin, or the bobbin has too little tension. Before you touch any dial, rethread the upper thread with the presser foot up, rethread the bobbin, clean lint from the tension path and bobbin area, and fit a fresh needle. If it still shows, lower the upper tension in small steps until the back of a satin stitch sample has about one-third bobbin thread down the middle.

Bobbin thread shows on top of embroidery when the upper thread pulls too tight against the bobbin, or when the bobbin thread is not held firmly enough. Do not reach for the tension dial first. Threading, lint and the needle can cause the same symptom, so work through the checks below in order and change a tension setting only when they come up clean.

Brother’s manual is the main example here, because its tension and troubleshooting pages spell out each step. This site is not affiliated with Brother or any other maker.

Why bobbin thread ends up on top

Every stitch is made by two threads. The top thread comes down through the needle, the bobbin thread runs underneath, and tension on each thread decides where they link up. In plain sewing, balanced tension links them in the middle of the fabric layers. Embroidery is set up differently: the top thread should cover the surface and show a little on the back, while the bobbin thread stays on the back.

When the top thread is pulled too tight, or the bobbin thread is held too loosely, the balance tips and the bobbin thread gets dragged up to the front. You see bobbin thread, often white, showing through the top thread on the surface of the design.

Brother’s manual describes it the same way. A little bobbin thread on the right side of the fabric means the upper thread is too tight. It also says a wrongly threaded bobbin can make the upper thread seem too tight, and that changing the upper tension then makes no difference.

Read the back of your stitching first

Before you change anything, check what the back looks like. Stitch a sample with a satin stitch, such as a block letter or a small satin column, on a scrap of the same fabric, stabilizer, needle and thread you are using for the job. A dark top thread with white bobbin thread makes the balance easy to see.

Turn it over. An embroidery blog describes a well-balanced satin stitch as roughly one-third bobbin thread running down the middle of the back, with the other two-thirds top thread split between the two sides. Rocky Mountain Sewing, a sewing retailer, gives the same picture in general terms: top thread covers about two-thirds of the back, with the bobbin thread in the center. Treat this as a rule of thumb, since Brother’s manual only says that, at correct tension, the upper thread slightly shows on the back.

What you see	What it usually means
About one-third bobbin thread in the middle of the back, no bobbin thread on top	Balanced. Leave the tension alone.
Bobbin thread shows on top, or the bobbin band on the back is much wider than about one-third	Upper thread too tight, or bobbin thread too loose
Loops on top, or top thread visible across the back and slack stitches	Upper thread too loose

A sample like this is worth the two minutes. It shows the problem on scrap fabric instead of on the shirt.

Fix it in this order

Many guides jump straight to the tension dial. One embroidery blogger advises against that and says to change the upper tension first only if you have just altered something on the machine, such as the thread weight. Brother’s manual agrees on the order: check the upper and bobbin threading first, then adjust tension. Try these steps in order.

Rethread the upper thread with the presser foot up. Brother’s manual says to raise the presser foot first, because with the foot down a shutter in the thread path is closed and the machine cannot be threaded. The same blogger adds that threading with the foot down can leave the thread out of the tension discs. Also check the spool. Thread that has snagged around the base of the spool, a guide or itself adds drag that can pull bobbin thread up.
Rethread the bobbin. Brother’s troubleshooting page for an over-tight upper thread blames a wrongly threaded bobbin. The symptoms are bobbin thread on top, an upper thread that looks like a single straight line, an upper thread that feels tight and pulls out when tugged, wrinkles in the fabric, and upper tension changes that make no difference. The fix is to reinstall the bobbin. In Brother’s manual, the thread has to slide into the bobbin case’s tension spring, and you hold the bobbin down lightly while the thread unwinds. In that manual the thread unwinds to the left, so check the direction in your own, and use a bobbin that is wound evenly.
Clean the thread path and the bobbin area. Lint or broken thread in the tension discs effectively raises the upper tension. Brush what you can reach of the path. The same blogger also runs unwaxed dental floss through the thread guides, always following the thread’s normal direction of travel. Never pull the top thread backward out of the machine, because that can upset the tension discs. Then switch the machine off and unplug it, and clean the bobbin case area with a brush or vacuum as your manual describes. Brother says not to oil the bobbin case, and never to use a bobbin case that is scratched or has a burr. Our machine maintenance guide covers the routine.
Fit a fresh needle. A dull or bent needle, or one that is too big for the job, makes a bigger hole, and bobbin thread can show through it. Brother’s manual also says that if the needle and thread are wrong for the fabric, the tension cannot be adjusted correctly. Our needle guide explains sizes and when to change them.
Check the bobbin thread itself. Designs are usually made for 40 wt top thread, and recommended bobbin thread is almost always 60 wt or finer. Some machines use 90 wt, and a different weight than your machine expects can change stitch quality. If the trouble starts as soon as you load a new bobbin, try another one to rule out a bad winding or a burr. On Brother machines, pre-wound and self-wound bobbins may need different bobbin cases. Our thread guide covers bobbin thread weights.
Reset the tension, then loosen the upper thread a little. Return the upper tension to its standard setting first. If bobbin thread still shows, lower the upper tension number in small steps and stitch a sample after each change. Brother warns that very loose upper tension can make the machine stop mid-design.
Adjust the bobbin case tension only as a last resort. Read your manual first, and do not touch the screw before steps 1 to 6 are done. One embroidery blogger lists this as a step to try only if nothing else works. Brother’s manual says the bobbin case with no color on its screw is the one meant for adjusting, and it is the case to use with bobbin thread other than the embroidery bobbin thread packed with the machine. You turn only the slotted screw, never the Phillips one. A small turn of about 30 to 45 degrees clockwise raises the bobbin tension, and you never force it. Remove the bobbin first, stitch a sample after each tiny change, and make a note of where the screw started. Other makers’ bobbin cases and multi-needle machines can differ, so follow your manual.
Rule out the design and the machine. Try a different design file, then restart the machine. Look over the needle plate for nicks around the needle hole, which the blogger rates as unlikely but possible. If bobbin thread still shows, a repair dealer can check for timing problems or a damaged bobbin case.

Which way to turn which setting

Symptom	Upper tension	Bobbin tension
Bobbin thread shows on top	Lower the number (loosen)	Tighten a little, as a last resort
Loops on top, with no bobbin thread on the back	Raise the number (tighten)	Loosen a little, as a last resort
Upper thread visible on the back, slack stitches	Raise the number (tighten)	Leave it alone

Brother’s troubleshooting page puts the threading check first and the tension change second, and says to test on scrap fabric that matches your project. If the upper thread shows on the back, rethread the upper thread before you raise the tension.

Where Brother puts the tension setting

If you own a Brother such as the PE800, PE900 or SE700, the checks above still apply, but the tension steps here come from a Brother operation manual for a sewing and embroidery combination machine. Your menus, button names and bobbin case parts may look different. In that manual, you tap the thread tension icon on the embroidery screen to adjust one design, or change the embroidery tension value in the settings screen to adjust every design. Use the per-design setting for fine-tuning, and the overall setting for a general problem. Check your own model’s manual for where the buttons are.

Fixing a design that already shows bobbin thread

If the hoop is still on the machine, back the machine up and restitch the area so new top thread covers the exposed bobbin thread. If you have already unhooped, a fine-tipped permanent marker or permanent fabric marker in a matching color can hide the bobbin thread. Try it on scrap first, because ink can bleed badly into fabrics such as terry cloth.

If a machine will not settle down and you need to finish a job, one blogger suggests winding a bobbin with thread that matches the top color, so any bobbin thread that peeks through is less noticeable. Matching is also worth doing when the back of the work will be seen, as with free-standing lace.

Stop it happening again

Stitch a sample on scrap with the real fabric, stabilizer and thread before every important job.
Change the needle regularly. Our needle guide says how often.
Clean the bobbin area regularly, and more often with linty or messy fabrics.
Use the bobbin thread weight your manual names. Our bobbin thread glossary entry explains what it is and why it is finer.
If your thread breaks or snaps while you chase the tension, read our guide to embroidery thread that keeps breaking.

Frequently asked questions

Why is my bobbin thread showing on top of my embroidery?

The upper thread is pulling too tight against the bobbin, or the bobbin thread is not held with enough tension. The usual causes are a badly threaded upper thread or bobbin, lint in the tension discs or bobbin area, and a dull or wrong-size needle. Rethread and clean before you change any tension setting.

Should I tighten or loosen the top tension if the bobbin thread shows on top?

Loosen it, by lowering the upper tension number in small steps. Brother's manual says that when a little bobbin thread appears on the right side, the upper thread is too tight, so you loosen it. It also says to rethread the bobbin first, because a badly threaded bobbin can make the upper thread look too tight.

How should the back of machine embroidery look?

On a satin stitch, roughly one-third of the back should be bobbin thread running down the center, with top thread making up the other two-thirds on either side. A sewing retailer's thread guide puts it the same way: top thread across about two-thirds of the back, with the bobbin thread in the middle.

What bobbin thread should I use for machine embroidery?

Use a bobbin thread finer than the 40 wt top thread. Brother's own is 60 wt, and some machines call for 90 wt. Your manual is the final word, because the wrong weight changes the balance of the stitch.

Can I fix bobbin thread that already shows on finished embroidery?

If the hoop is still on the machine, you can stitch the design area again so top thread covers the bobbin thread. You can also color the bobbin thread with a fine permanent marker, but try it on scrap first because the ink can bleed on fabrics such as terry cloth.