Manufacturer · Fashion & Home Accessories
Flat metal buttons are among the cleanest buttons a garment can have: a smooth face without relief, a slim profile and a shank underneath that hides the stitching. Polkom is a manufacturer of metal buttons and keeps flat metal shank buttons always in stock in five sizes – 15, 18, 20, 22 and 25 mm – and in four colours: gold, nickel (nickel free), gunmetal and black oxide, as well as in matte versions. This means you can take a sample, test a style or top up a production run without waiting for a made-to-order batch.
In this article you will see what a flat metal button looks like, which size suits which garment, how to choose colour and surface and what to include in your inquiry.
What is a flat metal shank button
A flat metal button has a level or only very slightly curved face, with no holes and no decoration. Instead of holes it has a shank (a small loop) underneath, through which the thread passes. That is why no stitching is visible from the front – only the clean metal surface remains. This is the difference from the classic 2-hole or 4-hole metal button and from the half-dome shank button, which is more voluminous and more noticeable.
The shank also has a practical role: it lifts the button above the fabric, so that thicker materials – wool, tweed, bouclé or dense knitwear – lie comfortably under the button when the garment is buttoned. You will find more about how the shank is built and about the types of shanks in the article metal shank buttons.
Always in stock: five sizes and four colours
Most metal buttons are made to order – with a choice of shape, finish and often a logo. Flat metal shank buttons are different: we keep them permanently in stock as a core style that fits many collections. This is convenient when:
- you are making a sample or prototype and want to see the button on the real garment;
- you are sewing a small run or a capsule collection and do not need a custom-designed button;
- you are topping up a run – you are short of buttons for a few pieces or need spare buttons;
- you are repeating a style from a previous season and want the same button in the same colour.
Sizes of flat metal buttons
The available sizes cover the most common positions on a garment – from the sleeve and cuff to the front of a coat. Lignes (L) are calculated with the formula L = mm / 0.635 and rounded to the nearest standard value.
| Diameter (mm) | Lignes (L) | Typical use |
|---|---|---|
| 15 | 24L | jacket sleeve, cuff, dress, blouse, light cardigan |
| 18 | 28L | dress, cardigan, overshirt, pockets |
| 20 | ≈32L | women’s blazer, jacket, blazer dress |
| 22 | ≈36L | blazer, jacket, light trench coat |
| 25 | ≈40L | coat, outerwear jacket, statement button |
If you measure buttons in lignes or convert a size from a tech pack, use the table in the article button sizes in lignes and mm.
Colours: gold, nickel, gunmetal and black oxide
- Gold – a warm, polished tone; a classic on navy, black, beige and camel fabrics.
- Nickel (nickel free) – a light silvery colour. The name describes only the colour: the finish is nickel free, like all our metal finishes.
- Gunmetal – a dark grey metallic tone, softer than black; works on grey, graphite, olive and denim.
- Black oxide – deep black with a metallic sheen; a tone-on-tone button on black fabric or a graphic contrast on light fabric.
- Matte versions – for example matte gold and matte gunmetal, for a calmer, more modern look.
How to match the button colour to the fabric colour is explained in detail in the article how to choose the colour of a metal button. For the dark tones, see also what gunmetal is and the types of black finish.
Polished or matte: how the surface changes the button
On a flat button the surface is more visible than on any other shape, because there is no relief to scatter the light. A polished finish reflects like a mirror – the button looks lighter, brighter and more formal. A matte finish diffuses the light: the colour is more even, quieter and more modern, and fingerprints are harder to notice on the surface.
A practical rule: polished gold for classic and eveningwear, matte gold and matte gunmetal for everyday and minimalist collections, for wool fabrics and for garments where the button should be present but not dominant. A comparison of all surfaces is in the article matte, satin, brushed or polished.
Minimalist style: blazer, coat and dress
The flat metal button is the choice for designers who want metal to be a detail, not an ornament. It does not compete with the cut, the texture of the fabric or the print – it underlines the line of the front.
Blazer and jacket
For the front of a women’s blazer, 20 or 22 mm are chosen most often, and 15 mm of the same style and colour for the sleeve. Gold on navy or black fabric gives the classic blazer look; nickel (nickel free) and gunmetal look more urban and contemporary. How many buttons you need and how they are placed on the front and sleeve is described in the article metal buttons for blazers and jackets.
Coat
On coats, 25 mm on the front and 18 or 20 mm for the pockets, belt or sleeve work best. The shank leaves room for the thick fabric, and the flat face does not visually weigh down the large surfaces of the coat. For choosing size and weight for coats, see metal buttons for coats.
Dress, blouse and cardigan
On dresses and blouses, flat buttons of 15 and 18 mm look almost like jewellery – a row of buttons down the front, on the shoulder or on the cuff. Black oxide on a black dress creates a tone-on-tone effect, while matte gold on beige or cream adds warmth without looking obtrusive. On knitted cardigans the shank keeps the stitches from stretching around the button.
Flat button or another shape?
The flat shape is not the only option for a clean look. If you are undecided, compare it with the other metal buttons:
- 2-hole or 4-hole button – the stitching is visible at the front and the button sits lower on the fabric; suitable for shirts and lighter materials.
- Half-dome shank button – a more voluminous, more decorative button that catches more light.
- Embossed or crest button – for classic, uniform and nautical styles.
- Logo button – when the button should carry the brand; made to order.
The flat shank shape is also available in smaller sizes for shirts – see the article metal shirt buttons, which covers sizes from 9 to 12.5 mm.
Sewing on and care
A shank button is sewn on through the loop: the thread passes through several times and is finally wound around the neck so that it does not loosen. On thick fabrics, leave a slightly longer thread neck so the button can pass freely through the buttonhole. The buttonhole should be slightly larger than the button diameter – details in the article buttonhole size.
Garments with metal buttons should be washed at a lower temperature on a delicate cycle, preferably turned inside out. It is best to iron around the buttons rather than directly over them. More tips are in the article caring for metal buttons in the wash.
How to order flat metal buttons
To prepare a quote, please include in your inquiry:
- the size – 15, 18, 20, 22 or 25 mm (or several sizes for the different positions on the garment);
- the colour – gold, nickel (nickel free), gunmetal or black oxide;
- the surface – polished or matte;
- the approximate quantity for each size and colour;
- the type of garment – blazer, coat, dress or another item, so we can recommend the right size.
If you need a finish outside the stock colours, browse the colour chart of metal finishes. The price depends on size, finish and quantity, so contact us for a quote.
Flat metal buttons from the manufacturer
Polkom is a Bulgarian manufacturer of buttons and accessories for fashion, furniture, footwear and bags, based in Sofia, with over 30 years of experience. All our metal finishes are nickel free. Flat metal shank buttons are always in stock in sizes 15, 18, 20, 22 and 25 mm and in gold, nickel, gunmetal and black oxide, including matte versions. Browse the metal buttons in our catalogue and tell us which size and colour you need.
