Data
UK filament price index: May 2026
In May 2026 the median PLA spool cost £12.99/kg, unchanged on April, across 376 listings. Across all filament the median was £15.19/kg, up 1.3% on April.
- all filament, median
- £15.19/kg
- materials ranked
- 28
- listings
- 2,402
- figures as of
- 6 Oct 2026
This is the archived index for May 2026. See the latest month.
From 2,402 filament listings on Amazon UK and Eryone UK, as of 6 Oct 2026. Updated every night.
Key findings, May 2026
- All filament: a median of £15.19/kg in May 2026, up 1.3% on April (up 0.4% like for like).
- PETG Dual/Tri was the cheapest material per kg (median £11.99); Nylon the dearest (£49.99).
- PETG Dual/Tri moved most: up 18.6% like for like on April.
- The cheapest PLA brand per kg was SUNLU, at a median of £7.00, 46% below the PLA median.
- Black Friday 2025 (20 Nov 2025 to 1 Dec 2025) was the deepest sale: filament prices fell a median 5.3% below their usual price, and 57% of listings were at least 5% off.
- Multi-packs of PLA cost a median £9.63/kg, 31% less than single spools.
Filament price leaderboard, May 2026
Every material with enough listings, cheapest median per kg first, against the all-filament benchmark. Switch tabs for buying and bulk figures.
What a kilogram of each material typically costs, and which way it's moving.
| 12-month trend | |||||||
|---|---|---|---|---|---|---|---|
| Benchmark, not ranked | All filament | £15.19 | up1.3% | up0.4% | — | 2,402 | |
| Rank 1 | PETG Dual/Tri | £11.99 | up17.7% | up18.6% | — | 11 | |
| Rank 2 | PLA | £12.99 | unchanged0.0% | down0.3% | — | 376 | |
| Rank 3 | PETG | £12.99 | up2.0% | up2.5% | — | 275 | |
| Rank 4 | PLA Translucent | £12.99 | down7.1% | down3.6% | — | 31 | |
| Rank 5 | PLA Rainbow | £13.36 | unchanged0.0% | unchanged0.0% | — | 26 | |
| Rank 6 | PLA Matte Twist | £13.99 | unchanged0.0% | up2.4% | — | 13 | |
| Rank 7 | PLA+ | £14.39 | up1.1% | up1.0% | — | 290 | |
| Rank 8 | PLA Matte | £14.99 | up4.0% | up0.6% | — | 270 | |
| Rank 9 | PETG Translucent | £15.14 | down5.8% | down2.2% | — | 14 | |
| Rank 10 | PLA Silk | £15.49 | up3.3% | up1.2% | — | 124 | |
| Rank 11 | PLA Glitter | £15.99 | unchanged0.0% | down0.9% | — | 150 | |
| Rank 12 | PLA Silk Twist | £16.66 | up10.0% | up0.9% | — | 10 | |
| Rank 13 | PLA Matte Gradient | £16.99 | up6.3% | down0.2% | — | 48 | |
| Rank 14 | PLA Marble | £16.99 | unchanged0.0% | down2.9% | — | 33 | |
| Rank 15 | PLA Silk Dual/Tri | £17.99 | unchanged0.0% | down0.5% | — | 309 | |
| Rank 16 | PLA Matte Dual/Tri | £17.99 | unchanged0.0% | up1.4% | — | 89 | |
| Rank 17 | PLA Matte Rainbow | £18.13 | down1.9% | up0.4% | — | 36 | |
| Rank 18 | PLA Glow | £18.49 | up2.6% | down0.7% | — | 58 | |
| Rank 19 | PLA Silk Gradient | £18.99 | up5.6% | up3.6% | — | 21 | |
| Rank 20 | PLA Silk Rainbow | £19.99 | up11.1% | up0.6% | — | 73 | |
| Rank 21 | PLA Wood | £20.99 | unchanged0.0% | unchanged0.0% | — | 18 | |
| Rank 22 | PETG-CF | £20.99 | unchanged0.0% | up0.6% | — | 7 | |
| Rank 23 | ABS-CF | £22.99 | unchanged0.0% | unchanged0.0% | — | 10 | |
| Rank 24 | ABS | £23.99 | unchanged0.0% | down1.1% | — | 29 | |
| Rank 25 | ASA | £25.99 | up13.0% | up1.1% | — | 28 | |
| Rank 26 | TPU | £30.99 | unchanged0.0% | down0.9% | — | 37 | |
| Rank 27 | Carbon Fiber | £35.54 | unchanged0.0% | up3.8% | — | 5 | |
| Rank 28 | Nylon | £49.99 | unchanged0.0% | unchanged0.0% | — | 8 |
Ranked by median price per kg, cheapest first; "All filament" is every material together. The bar marks the median within the middle half of listings. "vs last month" compares medians; "like for like" follows the same listings in both months; "vs a year ago" compares the median with the same month last year. Highlighted cells are the best in each column. Materials need 5 listings to be ranked; tap a heading to sort.
What counts as a good price, and whether now is a good time to buy.
| Shop | |||||||
|---|---|---|---|---|---|---|---|
| Benchmark, not ranked | All filament | £12.73/kg | About usualup1.3% | £14.44 – £15.99 | — | −5.3% Black Friday 2025 | Every material |
| Rank 1 | PETG Dual/Tri | £11.99/kg | Dearer than usualup9.1% | £10.19 – £11.99 | XINGTONGZHILIAN £11.99/kg | −0.0% Prime Big Deal Days 2025 | PETG Dual/Tri deals |
| Rank 2 | PLA | £10.99/kg | About usualdown2.3% | £12.74 – £13.59 | SUNLU £7.00/kg | −5.0% Black Friday 2025 | PLA deals |
| Rank 3 | PETG | £10.48/kg | About usualup1.6% | £11.99 – £12.99 | YUANEANG £8.74/kg | −12.9% Black Friday 2025 | PETG deals |
| Rank 4 | PLA Translucent | £11.99/kg | Cheaper than usualdown13.3% | £12.99 – £15.99 | iSANMATE £12.99/kg | −5.0% Black Friday 2025 | PLA Translucent deals |
| Rank 5 | PLA Rainbow | £12.99/kg | About usualunchanged0.0% | £12.99 – £14.36 | YUANEANG £12.99/kg | −6.3% Black Friday 2025 | PLA Rainbow deals |
| Rank 6 | PLA Matte Twist | £12.99/kg | About usualunchanged0.0% | £11.01 – £15.20 | ERYONE £12.99/kg | −10.3% Black Friday 2025 | PLA Matte Twist deals |
| Rank 7 | PLA+ | £12.00/kg | About usualunchanged0.0% | £13.59 – £15.89 | JAYO £11.50/kg | −5.1% Black Friday 2025 | PLA+ deals |
| Rank 8 | PLA Matte | £12.50/kg | Dearer than usualup7.1% | £13.29 – £14.99 | Deeplee £11.00/kg | −8.2% Black Friday 2025 | PLA Matte deals |
| Rank 9 | PETG Translucent | £13.99/kg | Cheaper than usualdown5.3% | £13.99 – £16.99 | SUNLU £9.30/kg | −15.0% Black Friday 2025 | PETG Translucent deals |
| Rank 10 | PLA Silk | £13.58/kg | Dearer than usualup3.3% | £14.98 – £15.99 | NevsBye £9.99/kg | −0.0% Black Friday 2025 | PLA Silk deals |
| Rank 11 | PLA Glitter | £12.62/kg | About usualunchanged0.0% | £15.99 – £16.99 | eSUN £8.77/kg | −3.9% Black Friday 2025 | PLA Glitter deals |
| Rank 12 | PLA Silk Twist | £13.51/kg | Cheaper than usualdown5.3% | £15.14 – £21.99 | ERYONE £13.46/kg | −0.0% Prime Big Deal Days 2025 | PLA Silk Twist deals |
| Rank 13 | PLA Matte Gradient | £14.99/kg | Dearer than usualup3.0% | £15.99 – £17.99 | FLASHFORGE £14.38/kg | −0.0% Black Friday 2025 | PLA Matte Gradient deals |
| Rank 14 | PLA Marble | £15.19/kg | About usualunchanged0.0% | £15.18 – £17.99 | CC3D £14.49/kg | −15.7% Prime Big Deal Days 2025 | PLA Marble deals |
| Rank 15 | PLA Silk Dual/Tri | £14.44/kg | Dearer than usualup5.9% | £15.99 – £17.99 | YUANEANG £11.99/kg | −15.0% Black Friday 2025 | PLA Silk Dual/Tri deals |
| Rank 16 | PLA Matte Dual/Tri | £15.99/kg | About usualunchanged0.0% | £15.99 – £17.99 | eSUN £14.49/kg | −10.0% Black Friday 2025 | PLA Matte Dual/Tri deals |
| Rank 17 | PLA Matte Rainbow | £15.99/kg | Dearer than usualup4.9% | £14.99 – £18.49 | iSANMATE £14.99/kg | −2.6% Black Friday 2025 | PLA Matte Rainbow deals |
| Rank 18 | PLA Glow | £14.99/kg | Dearer than usualup8.8% | £15.99 – £18.99 | ZIRO £12.99/kg | −0.0% Black Friday 2025 | PLA Glow deals |
| Rank 19 | PLA Silk Gradient | £17.09/kg | Dearer than usualup5.6% | £16.64 – £18.99 | OVERTURE £18.04/kg | −5.6% Black Friday 2025 | PLA Silk Gradient deals |
| Rank 20 | PLA Silk Rainbow | £14.99/kg | Dearer than usualup13.6% | £17.50 – £19.99 | YUANEANG £9.85/kg | −5.0% Prime Big Deal Days 2025 | PLA Silk Rainbow deals |
| Rank 21 | PLA Wood | £16.44/kg | About usualunchanged0.0% | £17.34 – £22.49 | LVVJ3D £20.40/kg | −5.6% Black Friday 2025 | PLA Wood deals |
| Rank 22 | PETG-CF | £17.42/kg | Dearer than usualup12.3% | £14.95 – £20.99 | ERYONE £20.99/kg | −6.3% Prime Big Deal Days 2025 | PETG-CF deals |
| Rank 23 | ABS-CF | £22.99/kg | About usualunchanged0.0% | £22.99 – £22.99 | ERYONE £22.99/kg | — | ABS-CF deals |
| Rank 24 | ABS | £11.39/kg | About usualunchanged0.0% | £17.98 – £23.99 | YUANEANG £9.99/kg | −6.7% Black Friday 2025 | ABS deals |
| Rank 25 | ASA | £20.49/kg | Dearer than usualup13.0% | £20.34 – £25.99 | ANYCUBIC £14.99/kg | −12.2% Black Friday 2025 | ASA deals |
| Rank 26 | TPU | £26.92/kg | About usualunchanged0.0% | £30.99 – £30.99 | Amazon Basics £11.89/kg | — | TPU deals |
| Rank 27 | Carbon Fiber | £24.99/kg | About usualunchanged0.0% | £35.54 – £35.54 | ERYONE £35.54/kg | — | Carbon Fiber deals |
| Rank 28 | Nylon | £26.99/kg | About usualunchanged0.0% | £49.99 – £49.99 | ERYONE £49.99/kg | — | Nylon deals |
Ranked by median price per kg, cheapest first; "All filament" is every material together. "Good price" is the 25th percentile: cheaper than three in four listings. "Now vs usual" compares this month's median with the median of the months before it (up to a year); within ±3% counts as usual. "Best sale" is the deepest median discount in the last year. Highlighted cells are the best in each column. Materials need 5 listings to be ranked; tap a heading to sort, or filter "Now vs usual".
Multi-packs against single spools, cost per 100 g for quoting, and how much prices swing over a year.
| Benchmark, not ranked | All filament | £15.99 | £10.20 | down36.2% | 349 | £1.52 | 10.7% |
|---|---|---|---|---|---|---|---|
| Rank 1 | PETG Dual/Tri | £11.99 | — | — | — | £1.20 | 17.7% |
| Rank 2 | PLA | £13.99 | £9.63 | down31.2% | 93 | £1.30 | 6.7% |
| Rank 3 | PETG | £13.99 | £9.25 | down33.9% | 69 | £1.30 | 8.3% |
| Rank 4 | PLA Translucent | £12.99 | — | — | 1 | £1.30 | 23.1% |
| Rank 5 | PLA Rainbow | £13.72 | £11.67 | down14.9% | 3 | £1.34 | 10.5% |
| Rank 6 | PLA Matte Twist | £13.99 | — | — | — | £1.40 | 38.1% |
| Rank 7 | PLA+ | £15.19 | £10.92 | down28.1% | 73 | £1.44 | 16.9% |
| Rank 8 | PLA Matte | £15.99 | £11.00 | down31.2% | 62 | £1.50 | 12.8% |
| Rank 9 | PETG Translucent | £16.14 | — | — | 2 | £1.51 | 21.4% |
| Rank 10 | PLA Silk | £15.99 | £10.92 | down31.7% | 13 | £1.55 | 6.7% |
| Rank 11 | PLA Glitter | £15.99 | £17.50 | up9.4% | 3 | £1.60 | 6.3% |
| Rank 12 | PLA Silk Twist | £16.66 | — | — | — | £1.67 | 45.2% |
| Rank 13 | PLA Matte Gradient | £16.99 | — | — | — | £1.70 | 12.5% |
| Rank 14 | PLA Marble | £16.99 | — | — | — | £1.70 | 18.5% |
| Rank 15 | PLA Silk Dual/Tri | £17.99 | £13.25 | down26.3% | 9 | £1.80 | 12.5% |
| Rank 16 | PLA Matte Dual/Tri | £17.99 | — | — | 1 | £1.80 | 12.5% |
| Rank 17 | PLA Matte Rainbow | £18.27 | — | — | 1 | £1.81 | 23.3% |
| Rank 18 | PLA Glow | £18.49 | £20.00 | up8.2% | 8 | £1.85 | 18.8% |
| Rank 19 | PLA Silk Gradient | £18.99 | — | — | — | £1.90 | 14.1% |
| Rank 20 | PLA Silk Rainbow | £19.99 | £13.06 | down34.7% | 9 | £2.00 | 14.2% |
| Rank 21 | PLA Wood | £20.99 | — | — | — | £2.10 | 29.7% |
| Rank 22 | PETG-CF | £20.99 | — | — | — | £2.10 | 40.4% |
| Rank 23 | ABS-CF | £22.99 | — | — | — | £2.30 | 0.0% |
| Rank 24 | ABS | £23.99 | — | — | 1 | £2.40 | 33.4% |
| Rank 25 | ASA | £25.99 | — | — | — | £2.60 | 27.8% |
| Rank 26 | TPU | £30.99 | — | — | 1 | £3.10 | 0.0% |
| Rank 27 | Carbon Fiber | £35.54 | — | — | — | £3.55 | 0.0% |
| Rank 28 | Nylon | £49.99 | — | — | — | £5.00 | 0.0% |
Ranked by median price per kg, cheapest first; "All filament" is every material together. Multi-packs include spools of 2 kg or more. Each figure needs three listings. "Per 100 g" is the filament in a 100 g print at the median price. "12-month swing" is how far the monthly median moved between its low and high. Highlighted cells are the best in each column. Materials need 5 listings to be ranked; tap a heading to sort.
How prices moved
The four materials with the most listings and the all-filament benchmark, month by month.
Cheapest brands per kg
The brands with the lowest median price per kg in May 2026, by material.
| Rank 1 | SUNLU | £7.00/kg | down46.1% | 6 |
|---|---|---|---|---|
| Rank 2 | YUANEANG | £9.99/kg | down23.1% | 12 |
| Rank 3 | LANDU | £10.72/kg | down17.5% | 12 |
| Rank 4 | 3DHoJor | £10.92/kg | down15.9% | 4 |
| Rank 5 | Kingroon | £11.00/kg | down15.3% | 21 |
| Rank 6 | Amazon Basics | £11.89/kg | down8.5% | 2 |
| Rank 7 | ANYCUBIC | £11.89/kg | down8.5% | 73 |
| Rank 8 | OVERTURE | £11.99/kg | down7.7% | 23 |
| Rank 9 | eSUN | £12.99/kg | unchanged0.0% | 39 |
| Rank 10 | JAYO | £12.99/kg | unchanged0.0% | 12 |
| Rank 1 | YUANEANG | £11.99/kg | down33.4% | 12 |
|---|---|---|---|---|
| Rank 2 | NevsBye | £13.13/kg | down27.0% | 12 |
| Rank 3 | 3DHoJor | £13.41/kg | down25.5% | 14 |
| Rank 4 | ANYCUBIC | £13.58/kg | down24.5% | 13 |
| Rank 5 | Sovol | £13.99/kg | down22.2% | 3 |
| Rank 6 | Kingroon | £14.44/kg | down19.7% | 3 |
| Rank 7 | RepRapper | £14.99/kg | down16.7% | 9 |
| Rank 8 | LANDU | £15.19/kg | down15.6% | 13 |
| Rank 9 | ELEGOO | £15.49/kg | down13.9% | 8 |
| Rank 10 | ZIRO | £15.49/kg | down13.9% | 8 |
| Rank 1 | JAYO | £11.50/kg | down20.1% | 20 |
|---|---|---|---|---|
| Rank 2 | ANYCUBIC | £12.74/kg | down11.5% | 21 |
| Rank 3 | SUNLU | £12.99/kg | down9.7% | 86 |
| Rank 4 | NevsBye | £13.08/kg | down9.1% | 2 |
| Rank 5 | OVERTURE | £13.59/kg | down5.6% | 44 |
| Rank 6 | RepRapper | £14.39/kg | unchanged0.0% | 2 |
| Rank 7 | ELEGOO | £14.79/kg | up2.8% | 6 |
| Rank 8 | FLASHFORGE | £15.29/kg | up6.3% | 14 |
| Rank 9 | eSUN | £15.99/kg | up11.1% | 52 |
| Rank 10 | ERYONE | £23.99/kg | up66.7% | 42 |
| Rank 1 | YUANEANG | £8.74/kg | down32.7% | 14 |
|---|---|---|---|---|
| Rank 2 | GratKit | £9.00/kg | down30.7% | 15 |
| Rank 3 | LANDU | £9.46/kg | down27.2% | 8 |
| Rank 4 | SUNLU | £9.50/kg | down26.9% | 13 |
| Rank 5 | NevsBye | £9.94/kg | down23.5% | 2 |
| Rank 6 | Kingroon | £10.48/kg | down19.3% | 4 |
| Rank 7 | Sovol | £10.99/kg | down15.4% | 8 |
| Rank 8 | TECBEARS | £11.36/kg | down12.5% | 18 |
| Rank 9 | JAYO | £11.39/kg | down12.3% | 9 |
| Rank 10 | ANYCUBIC | £11.75/kg | down9.5% | 39 |
| Rank 1 | Deeplee | £11.00/kg | down26.6% | 45 |
|---|---|---|---|---|
| Rank 2 | NevsBye | £11.33/kg | down24.4% | 9 |
| Rank 3 | iSANMATE | £11.67/kg | down22.1% | 2 |
| Rank 4 | YUANEANG | £11.99/kg | down20.0% | 3 |
| Rank 5 | ANYCUBIC | £12.83/kg | down14.4% | 12 |
| Rank 6 | JAYO | £12.99/kg | down13.3% | 9 |
| Rank 7 | SUNLU | £13.65/kg | down8.9% | 26 |
| Rank 8 | ZIRO | £13.99/kg | down6.7% | 17 |
| Rank 9 | ELEGOO | £14.22/kg | down5.1% | 9 |
| Rank 10 | GratKit | £14.99/kg | unchanged0.0% | 7 |
| Rank 1 | eSUN | £8.77/kg | down45.2% | 9 |
|---|---|---|---|---|
| Rank 2 | OVERTURE | £12.67/kg | down20.8% | 4 |
| Rank 3 | ZIRO | £14.99/kg | down6.3% | 27 |
| Rank 4 | chitu systems | £16.24/kg | up1.6% | 4 |
| Rank 5 | ANYCUBIC | £16.98/kg | up6.2% | 4 |
| Rank 6 | ELEGOO | £17.99/kg | up12.5% | 12 |
| Rank 7 | TINMORRY | £17.99/kg | up12.5% | 4 |
| Rank 8 | Stronghero3D | £19.27/kg | up20.5% | 6 |
| Rank 9 | ERYONE | £19.99/kg | up25.0% | 73 |
| Rank 10 | FLASHFORGE | £19.99/kg | up25.0% | 4 |
| Rank 1 | NevsBye | £9.99/kg | down35.5% | 4 |
|---|---|---|---|---|
| Rank 2 | ANYCUBIC | £13.28/kg | down14.3% | 10 |
| Rank 3 | SUNLU | £13.99/kg | down9.7% | 21 |
| Rank 4 | JAYO | £14.24/kg | down8.1% | 3 |
| Rank 5 | ZIRO | £14.49/kg | down6.5% | 16 |
| Rank 6 | OVERTURE | £14.99/kg | down3.2% | 9 |
| Rank 7 | AMOLEN | £15.12/kg | down2.4% | 2 |
| Rank 8 | ELEGOO | £15.99/kg | up3.2% | 13 |
| Rank 9 | LANDU | £16.99/kg | up9.7% | 3 |
| Rank 10 | Eono | £19.99/kg | up29.1% | 3 |
| Rank 1 | eSUN | £14.49/kg | down19.5% | 2 |
|---|---|---|---|---|
| Rank 2 | GratKit | £14.99/kg | down16.7% | 7 |
| Rank 3 | ZIRO | £15.99/kg | down11.1% | 12 |
| Rank 4 | SUNLU | £16.14/kg | down10.3% | 8 |
| Rank 5 | OVERTURE | £16.99/kg | down5.6% | 4 |
| Rank 6 | R3D | £17.99/kg | unchanged0.0% | 5 |
| Rank 7 | ERYONE | £26.99/kg | up50.0% | 46 |
| Rank 8 | Goto Guard | £35.06/kg | up94.9% | 3 |
Every month's brand ranking is in the brands CSV.
How deep were the sales?
Prime Day, Black Friday and other events in the last year, ranked by how far prices really fell.
| By material | ||||
|---|---|---|---|---|
| Rank 1 | Black Friday 202520 Nov 2025 to 1 Dec 2025 · 1628 listings | 5.3%all filament | 57% |
|
| Rank 2 | Prime Big Deal Days 20257 Oct 2025 to 8 Oct 2025 · 1283 listings | 0.0%all filament | 45% |
|
The discount is each listing's lowest price during the event against its own median over the 30 days before, from our price history, not the retailer's "was" price.
Filament prices: common questions
Answers from the May 2026 figures.
How much does PLA filament cost in the UK?
In May 2026 the median PLA listing on Amazon UK and Eryone UK cost £12.99/kg, and the middle half of listings cost between £10.99 and £15.99 per kg. That's from 376 listings in SpoolDeal's price index, as of 31 May 2026.
What is a good price for PLA filament per kg?
Under £10.99/kg is cheaper than three in four PLA listings we track (May 2026). The cheapest brand per kg was SUNLU, at a median of £7.00/kg. Compare by price per kg, not per spool: spool sizes and multi-packs vary.
Is 3D printer filament getting cheaper?
Across all filament the median was £15.19/kg in May 2026, up 1.3% on the month before. Like for like, following the same listings, prices were up 0.4%.
Are filament multi-packs cheaper than single spools?
PLA multi-packs cost £9.63/kg, 31% less than single spools (£13.99/kg); PLA Silk Dual/Tri multi-packs cost £13.25/kg, 26% less than single spools (£17.99/kg); PLA+ multi-packs cost £10.92/kg, 28% less than single spools (£15.19/kg), in May 2026.
How much do filament prices really drop on Prime Day and Black Friday?
Black Friday 2025: prices fell a median 5.3% below their usual price, with 57% of listings at least 5% off. Prime Big Deal Days 2025: prices barely moved from their usual price, with 45% of listings at least 5% off. The usual price is each listing's own median over the 30 days before the event, from our price history, not the retailer's "was" price.
Can I use these figures?
Yes. The index and its CSV are free to reuse under CC BY 4.0: credit "SpoolDeal UK filament price index" and link to the month's page. Press and data questions: james@trinkify.co.uk.
Methodology
What's covered. The filament listings SpoolDeal tracks on Amazon UK and Eryone UK, not every UK shop. We check prices through the day and keep every change, so each listing has a price for every day: the one in effect at noon (UTC). It's the lowest price on offer, including Prime members' prices where those are lower, with VAT. Dividing by the filament weight on the listing (a multi-pack counts every spool) gives a price per kilogram.
How a month is worked out. A listing's price for a month is the median of its days; it needs at least seven days of prices. A material's figure is the median across its listings, and "All filament" is the median across every listing. Listings under £4/kg or over £250/kg are left out as mispriced. Materials are grouped as the listings name them (PLA, PLA+, PLA Silk and so on).
Change. "vs last month" and "vs a year ago" compare medians, so they move when listings come and go. "Like for like" follows only the listings priced in both months: the geometric mean of each listing's own change, the method the ONS uses for the Consumer Prices Index. "Now vs usual" compares a month's median with the median of the months before it, up to a year.
Brands, multi-packs and sales. A brand is ranked on the median of its listings of that material (at least two). Multi-packs include single spools of 2 kg or more; the single-spool and multi-pack figures each need three listings. A sales event's discount compares each listing's lowest price during the event with its own median over the 30 days before (at least 14 days of prices); it never uses the retailer's "was" price. Event dates are the retailer's announced dates.
Revisions. The last 13 months are recomputed every night from the full history, so the running month is provisional and a recent month can shift slightly as late price changes arrive. Older months are frozen, and every month keeps its own page.
Reuse. Free under CC BY 4.0: credit "SpoolDeal UK filament price index" with a link to the month's page. Data: materials CSV and brands CSV. Questions: james@trinkify.co.uk.
Waiting for cheaper filament?
Open any reel and set the price you want to pay. We check it through the day and email you when it gets there. Free, and you can switch it off any time.