Galaxy Note 20 Ultra Battery Replacement: DIY Guide
A Galaxy Note 20 Ultra battery replacement runs about $20 to $40 in parts if you do it yourself, or $70 to $110 at a local repair shop. It is absolutely a DIY-doable job for a patient owner, and it is the smartest way to get another two or three years out of a phone that still has a gorgeous 6.9-inch display and a built-in S Pen.
Launched in 2020, most Note 20 Ultra units are now four-plus years and hundreds of charge cycles deep. That is exactly the point where the original 4500mAh cell starts to sag. Below is everything you need to diagnose the problem, decide who should do the work, and get the right part.
How to check your Galaxy Note 20 Ultra battery health
Samsung finally built a real battery-health readout into One UI, and the Note 20 Ultra can run it if it has been updated to One UI 5 or newer (Android 13). Here is the path:
- Open Settings
- Tap Battery and device care
- Tap Battery
- Tap Diagnostics, then Battery health
You will see a rating of Good, Normal, Weak, or a maximum-capacity percentage depending on your firmware. Anything below roughly 80% of the original design capacity means the cell is worn and a swap is worth it.
If your Note 20 Ultra is still on older firmware and shows no Diagnostics menu, do not guess. Install a free app like AccuBattery, then let it learn through a few full charge cycles. It estimates real-world capacity by measuring actual current in and out, and it is the most honest reading you will get without opening the phone. A cell that once held 4500mAh and now measures 3400mAh is telling you exactly what is wrong.
Signs your Galaxy Note 20 Ultra battery is failing
Battery wear rarely announces itself with one dramatic failure. Watch for a cluster of these symptoms:
- Galaxy Note 20 Ultra battery draining fast — you leave the house at 100% and you are hunting for a charger by mid-afternoon on light use.
- Sudden percentage drops, like falling from 40% to shutdown in minutes, especially in cold weather.
- The phone gets uncomfortably warm during ordinary tasks or wireless charging.
- Sluggish performance, because One UI quietly throttles the processor to protect a weak cell.
- The phone shuts down even though it still shows charge remaining.
- Galaxy Note 20 Ultra battery not charging past a certain point, or charging painfully slowly.
One warning you must never ignore: swelling. If the back glass starts lifting, the screen bulges, or the phone rocks on a flat table, stop charging it immediately. A swollen lithium-ion cell is a puncture risk and a fire hazard. Power the phone down, keep it away from anything flammable, and replace the battery promptly rather than continuing to charge a distended pack.
Galaxy Note 20 Ultra battery replacement cost
The Note 20 Ultra is out of Samsung's standard support window, so first-party service is limited and pricey where it still exists. Here is the realistic 2026 picture:
| Option | Typical 2026 cost | Notes |
|---|---|---|
| Samsung / authorized service | $70–$99 | Often no longer offered for a 2020 model; you may be quoted a flat "out-of-warranty" repair fee. |
| Local repair shop | $70–$110 | Labor plus part; ask whether they use a fresh cell or a pull. |
| DIY with a quality part | $20–$40 | Just the battery and adhesive; add a $10–$15 tool kit if you don't own one. |
When people search galaxy note 20 ultra battery replacement cost they are usually shocked at the gap between a $30 part and a $250-plus used-phone upgrade. That gap is the whole argument for repairing.
The exact replacement battery for the Note 20 Ultra
You need a 4500mAh Li-ion cell, Samsung part number EB-BN985ABY. It fits every Note 20 Ultra variant, sold as SM-N985F and SM-N985F/DS (4G) and the 5G models SM-N986B, SM-N986U, and SM-N986U1. All of them use the same physical pack, so you do not need to match your carrier — you only need to match the model family.
Be careful when shopping for a galaxy note 20 ultra oem battery. The Note 20 Ultra and the smaller Note 20 use different-capacity cells (4500mAh vs 4300mAh), so confirm the listing says 4500mAh and references the N985/N986 numbers. A zero-cycle premium cell with the correct capacity will restore full runtime; a mystery pull from an unknown seller often will not. You can browse verified replacement cells in the PhonePartPro replacement batteries collection, which ships fast from the US and is priced for both retail and wholesale repair buyers.
How to replace the Galaxy Note 20 Ultra battery yourself
Here is the honest part: this is a moderate-to-hard repair, and the hardest step is the very first one. Rate it a 6 out of 10. The Note 20 Ultra has a glued glass back and a battery held down with strong adhesive, so heat and patience matter more than muscle.
Step overview for how to replace the Galaxy Note 20 Ultra battery:
- Power down and, if possible, run the battery below 25% first — a charged lithium cell is more dangerous if nicked.
- Heat the back glass with a heat pad or hair dryer to soften the adhesive, then use a suction cup and thin picks to separate it. Go slowly to avoid cracking the glass.
- Disconnect the battery first. Once inside, remove the shield brackets and unplug the battery connector before touching anything else.
- Release the battery adhesive. Note 20 Ultra packs are stubborn; use adhesive-removal solvent or isopropyl alcohol around the edges and pull the stretch-release tabs slowly. Never pry a glued cell with a metal tool.
- Seat the new 4500mAh battery, reconnect the connector, and test before you seal.
- Re-adhere the back glass with fresh perimeter adhesive.
If you have never opened a glued-glass phone, budget an hour and watch a model-specific teardown video first. If the swelling is severe or the back glass is already cracked, a repair shop is the safer call.
After the swap: calibrate and watch for warnings
Samsung phones do not permanently lock out third-party batteries the way some brands do, but after a swap the on-screen percentage can read inaccurately until the phone relearns the new cell's true capacity. Run one calibration cycle: charge to 100%, leave it plugged in another 30 minutes, then use it down to automatic shutdown, and charge back to 100% uninterrupted. That one full cycle resets the fuel gauge.
You may also see the Diagnostics battery-health readout show a generic value or take a few cycles to settle — that is normal for a non-original cell and not a defect. There is no genuine-parts pop-up that disables features on the Note 20 Ultra.
One Note-specific tip: the S Pen and the productivity features that make this phone special are also heavy on the battery. Air Actions, Samsung DeX, split-screen multitasking, and constant note-taking all pull hard on the cell. If you are the kind of power user who bought a Note 20 Ultra precisely to work off it, a fresh battery will feel like a bigger upgrade than it would on a phone that mostly idles in a pocket.
Repair vs. upgrade: the green math
A worn battery is the single most common reason a perfectly good flagship gets retired. But nothing else about the Note 20 Ultra has aged badly — the 120Hz display, the 108MP camera, and the S Pen still hold up in 2026. Spending $20 to $40 on a cell instead of $300-plus on a replacement phone keeps a capable device in service and keeps one more slab of glass, rare metals, and lithium out of a landfill.
That is the entire philosophy behind repairing rather than replacing: the greenest phone is the one you already own. If you are weighing this against other Samsung models, our battery replacement by model guide compares costs and difficulty across the lineup, and the full replacement batteries collection covers Note, Galaxy S, and beyond.
FAQ
How much does a Galaxy Note 20 Ultra battery replacement cost?
Expect $20 to $40 for a quality replacement cell if you do it yourself, or $70 to $110 at a repair shop that includes labor. First-party Samsung service, where still offered for this 2020 model, tends to run $70 to $99.
How do I replace a Galaxy Note 20 Ultra battery?
Power down, heat and lift the glued glass back with a suction cup and picks, disconnect the battery connector first, release the adhesive under the cell with solvent and the stretch tabs, seat a new 4500mAh battery, test, then re-seal the back with fresh adhesive. It is a moderate-to-hard repair, roughly a 6 out of 10.
Why is my Galaxy Note 20 Ultra battery draining fast?
After four-plus years the original cell has lost capacity, so it simply holds less charge. Heavy S Pen use, DeX, high refresh rate, and background sync accelerate the drain. If the phone dies well before a full day on light use, the battery is worn and worth replacing.
What battery does the Galaxy Note 20 Ultra use?
A 4500mAh Li-ion cell, Samsung part EB-BN985ABY, fitting the SM-N985 (4G) and SM-N986 (5G) variants. Make sure any listing you buy states 4500mAh, because the smaller Note 20 uses a different 4300mAh pack.
Is it worth searching for Galaxy Note 20 Ultra battery replacement near me?
A local shop is convenient and a good choice if the back glass is cracked or the cell is badly swollen. But you will pay two to three times the parts cost for labor. If you are comfortable with a moderate repair, ordering the correct cell and doing it yourself is far cheaper.
Will a new battery trigger a warning on my Note 20 Ultra?
No feature-disabling genuine-parts lockout appears on the Note 20 Ultra. The battery percentage may read inaccurately until you run one full calibration cycle, and the Diagnostics health rating can take a few cycles to settle on a non-original cell. Both are normal.