The short answer
The Breville Bambino and Bambino Plus use a 54 mm portafilter, so you need a 54 mm bottomless portafilter - the same size that fits the Barista Express, Barista Pro, Infuser and Duo-Temp. A 58 mm portafilter will not lock into the group, and there is no adapter.
Breville sizing, plainly
Scroll the table sideways to see every column.
The Dual Boiler is the exception in Breville's range and takes the commercial 58 mm size. Everything else in the home line is 54 mm.
Quick picks
The answer first. Tap any row to jump to the full reasoning for that pick.
1. The one that fits
Normcore 54 mm Bottomless Portafilter
Entry tier · A naked portafilter for 54 mm Breville machines, with a basket included.
54 mm, made for the Breville platform, with a 16-18 g basket included.
This is the fitment answer. Normcore's 54 mm bottomless portafilter is made for Breville and Sage machines, and the compatibility list covers the Barista Pro (BES878), Barista Express (BES870XL), the Infuser (BES840XL) and the Duo-Temp (BES810BSS) - and the Bambino line uses the same 54 mm size.
It is 304 stainless with an anodized aluminum or solid walnut handle, and it comes with a 16-18 g basket.
That basket is doing as much work as the portafilter. Breville's stock baskets are serviceable, but a well-made unpressurized basket with evenly distributed holes gives you a puck whose resistance comes from the coffee rather than from the hardware.
The spouts are gone, so you see the underside of the basket during the shot. That is the whole point, and it is the fastest diagnostic in home espresso.
Specification
- Fits
- Breville 54 mm: Barista Express, Barista Pro, Infuser, Duo-Temp
- Material
- 304 stainless; anodized aluminum or walnut handle
- Basket
- 16-18 g included
What it does well
- Shows you exactly where the extraction is going wrong - nothing else does that
- Comes with a non-pressurized basket, which is the actual upgrade
- Fits the most common home machine platform in the US
Where it gives ground
- It will spray your kitchen while you learn
- Diagnoses problems; it does not fix them
- Useless without a grinder that can respond to what you see
Skip it if
Skip it if you are not willing to change your routine based on what you see. It shows problems; it does not solve them.
2. Buy this at the same time
Normcore WDT Tool V4
Entry tier · A retractable needle tool for breaking up clumps in the basket before tamping.
The portafilter will show you channeling; this is how you usually stop it.
The first thing a bottomless portafilter shows most people is channeling, and the most common cause of channeling is clumping in the basket.
The Normcore WDT V4 has nine needles with both 0.3 mm and 0.4 mm sets included, in 304 stainless with an anodized aluminum handle - and crucially it comes in 54 mm to match the Bambino's basket.
The needles retract with a twist so the tool survives a drawer rather than arriving bent, and they are soft enough not to scratch the basket you are stirring against.
Together the two purchases form a loop: see the problem, change the preparation, see whether it worked. That loop is how espresso gets better.
Specification
- Needles
- 9 needles; 0.3 mm and 0.4 mm sets included
- Material
- 304 stainless needles, anodized aluminum handle
- Mechanism
- Twist to extend or retract
- Sizes
- 54 mm and 58 mm
What it does well
- The cheapest meaningful improvement to an espresso shot, by some distance
- Retracting needles means it lives in a drawer without bending
- Two needle gauges cover fine and coarser grinds
Where it gives ground
- Adds a step to every single shot
- Needles will eventually bend whatever you do
- Does nothing at all for filter coffee
Skip it if
Skip it if you already own one in 54 mm. One needle tool is enough.
3. What to buy if it keeps channeling
Baratza Encore ESP
Entry tier · The Encore re-geared for espresso: the same 40 mm burrs on a dual-resolution collar.
If puck prep is right and it still sprays, the grinder is the limit.
The Bambino has no grinder, so the shot is entirely at the mercy of whatever you pair it with - and a bottomless portafilter will make that painfully visible.
The Encore ESP publishes approximately 20 microns per click across steps 1 to 20 for espresso, and roughly 90 microns per click across steps 21 to 40 for filter, on 40 mm M2 steel conical burrs made by Etzinger, held at 550 rpm.
That 20-micron figure is what lets you actually respond to what you see. With a coarse-stepped grinder, the correction you want often falls between two settings and you cannot reach it.
The burr housing is designed for easy removal to clean or shim, and shims are included.
Specification
- Burrs
- 40 mm M2 steel conical (Etzinger)
- Settings
- 40 stepped, dual resolution
- Espresso range
- Steps 1-20, 20 microns per click
- Filter range
- Steps 21-40, 90 microns per click
- Burr speed
- 550 rpm
What it does well
- 20 microns per click in the espresso range is real dialing resolution
- Redesigned burr housing makes cleaning and shimming easy
- Shims included in the box
Where it gives ground
- Still a stepped grinder - you cannot land between clicks
- Retention is normal-for-the-class, not low
- Same plastic body and noise as the Encore
Skip it if
Skip it if you already own a capable espresso grinder. Do not buy a second one out of habit.
4. Skip this - wrong platform entirely
De Longhi Dedica EC685
Budget tier · A six-inch-wide thermoblock machine with a pressurized 51 mm portafilter.
51 mm and pressurized: this upgrade barely exists for it.
Included because people searching for Breville accessories sometimes own a Dedica and assume the parts are interchangeable. They are not.
The Dedica uses a 51 mm pressurized portafilter with a 1 L tank, 15 bar pump and 1350 W thermoblock in a 5.9-inch-wide body.
51 mm has a far smaller accessory market than 54 mm, so bottomless portafilters and good baskets are much harder to find.
And the pressurized basket undermines the exercise: back-pressure is generated by a restricted wall rather than by the coffee, so what you would be watching is not really your puck's behavior.
Specification
- Portafilter
- 51 mm, pressurized
- Water tank
- 35 oz / 1 L
- Pump
- 15 bar
- Power
- 1350 W thermoblock
- Footprint
- 5.9 in W x 13 in D x 13 in H
What it does well
- Genuinely tiny - fits where nothing else will
- Forgiving with supermarket beans thanks to the pressurized basket
- Fast to heat
Where it gives ground
- The pressurized basket manufactures crema; it hides grind quality rather than rewarding it
- 51 mm is an accessory dead end compared with 54 mm or 58 mm
- Panarello-style frother, not a bare steam wand
Skip it if
Skip this whole upgrade path on a 51 mm pressurized machine. The machine is the limiting factor, not the portafilter.
Why this is the best first upgrade for a Bambino
The Bambino's unpressurized 54 mm basket already gives honest feedback about your grind - too coarse runs fast and thin, too fine chokes. What it cannot show you is *where* the water went.
A shot that runs at a reasonable speed can still be badly channeled, with water rushing through one part of the puck and barely touching the rest. Through spouts, that looks like a normal shot. Through a bottomless portafilter it looks like a jet firing sideways, and it is immediately obvious.
Since the Bambino has no grinder, its shot quality is entirely determined by what you pair it with and how you prepare the puck - which makes this feedback more valuable here than on an all-in-one machine.
What to look for during the shot
- 1First 5-8 seconds: the base of the basket should darken evenly as the puck saturates. Patchy darkening means uneven distribution.
- 2Around 8-12 seconds: droplets should appear across the base and merge into a single stream. A single jet appearing early is channeling.
- 3Mid-shot: one steady stream, ideally straight down. Sideways sprays are channels.
- 4Late shot: the stream turning pale is blonding, which is normal - stop shortly after it starts.
Fixing what you see
Channeling from one spot usually means a clump or a void in that area, which a needle tool addresses. Spraying around the edge usually means the dose is too small for the basket or the tamp was angled. Very fast, pale extraction throughout means the grind is too coarse.
If your distribution and tamping are consistent and it still channels, the remaining variable is the grinder - and on a Bambino that is the purchase to look at next.
The one downside
It makes a mess while you learn. Espresso goes where the channeling sends it, which for the first week or two may be your counter and occasionally your shirt. That is the tool working, and it stops.