Button, Coin and Watch Battery Codes: UK Retailer Guide

Button, coin and watch batteries are identified by several overlapping code systems. A customer may bring in a cell marked 377, SR626SW, CR2032, LR44, AG13 or A76, while the retailer's stock record uses a different manufacturer number. Some of those labels describe genuine cross-references; others describe cells that are only similar in size. Choosing by diameter alone can produce the wrong voltage, chemistry, thickness or discharge behaviour.

This guide explains a repeatable way to read miniature-battery codes, check equivalents and manage a retailer's range. It uses examples represented in the current 121 Wholesale catalogue, including Renata watch batteries and lithium coin cells, Maxell CR2016, CR2025 and CR2032 packs, and other button-cell formats. Current variants should always be confirmed on the live watch-battery collection and button-cell collection.

Button, coin and watch are shape or use descriptions

These everyday terms overlap, but they do not identify one chemistry:

• Button cell commonly describes a small, squat round cell, often alkaline or silver oxide.
• Coin cell commonly describes a wider, flatter lithium cell such as CR2032.
• Watch battery describes an application and sales category. Many watch cells are silver oxide, but a watch may use another chemistry or size.

The shape is only the starting point. The replacement must also match the device manufacturer's specified chemistry, voltage, dimensions, terminal arrangement and performance class.

Read the chemistry before the dimensions

Common prefix	Typical chemistry and nominal voltage	Example	Retail caution
CR	Lithium manganese dioxide, normally 3V	CR2032	Do not replace with a 1.5V cell merely because the diameter looks similar
SR	Silver oxide, normally about 1.55V	SR626SW	Check the drain suffix and manufacturer cross-reference
LR	Alkaline, normally 1.5V	LR44	An alkaline cell can share dimensions with a silver-oxide family but have different discharge behaviour

Nominal figures are not a permission to substitute. The device instructions and a current manufacturer replacement chart remain the authority. Medical devices, specialist instruments and sealed products may have tighter requirements than toys, calculators or general electronics.

Decode common CR lithium coin-cell numbers

In a four-digit CR code, the first two digits commonly indicate the nominal diameter in millimetres and the final two indicate nominal thickness in tenths of a millimetre. Therefore:

• CR2016 is approximately 20mm in diameter and 1.6mm thick;
• CR2025 is approximately 20mm in diameter and 2.5mm thick; and
• CR2032 is approximately 20mm in diameter and 3.2mm thick.

All three may fit the same circular outline, but they are not physically identical. A thinner cell can lose contact in a compartment designed for a thicker one. Forcing a thicker cell can damage the holder, casing or terminals. The capacity also differs by design, so a fit that appears possible does not prove correct performance.

The current range contains additional CR formats such as CR1025, CR1216, CR1220, CR1225, CR1616, CR1620, CR1632, CR2320, CR2325, CR2430 and CR2450N. Use the complete code. A suffix such as the "N" in CR2450N can identify a different case profile or contact arrangement; it should not be removed from the stock title or treated as ordinary CR2450 without manufacturer confirmation.

Understand numbered watch-battery references

Watch-battery packs frequently use a short number such as 315, 364, 371 or 377. Manufacturer cross-reference tables connect those numbers to IEC-style codes and other brands' labels. The relationship is useful, but it needs to preserve the complete code, including any high-drain or low-drain suffix.

Number family	Common IEC-style family shown in manufacturer charts	Stock-control note
315	SR716SW	Keep the 315 number and IEC reference searchable
317	SR516SW	Do not confuse with 377
319	SR527SW	Use the full five-digit size code
321	SR616SW	Verify thickness as well as diameter
357/303	SR44W or SR44SW family	Check the device's drain requirement; do not collapse every SR44 or LR44 label into one SKU
362/361	SR721SW or SR721W family	The suffix can matter
364/363	SR621SW family	Retain both the short number and IEC reference in lookup data
371/370	SR920SW or SR920W family	Use a manufacturer chart to select the correct drain version
377/376	SR626SW family	377 and 376 are commonly grouped, but the original device code should still be recorded
379	SR521SW	Do not transpose the final digits
390/389	SR1130W or SR1130SW family	Check high- or low-drain requirement
392/384	SR41W or SR41SW family	Similar dimensions do not make LR41 an automatic substitute
395/399	SR927SW or SR927W family	Use the exact suffix in technical records
397/396	SR726SW or SR726W family	Confirm the device manufacturer's replacement

The examples above follow the current Energizer battery cross-reference guide. They are a lookup aid, not a universal instruction to substitute every code shown in the same family. Retailers should use the latest chart for the stocked manufacturer and the original device specification.

Do not ignore W and SW drain suffixes

Silver-oxide watch cells may be offered in versions intended for different load profiles. Manufacturer charts commonly use W and SW suffixes to distinguish those types. A simple analogue watch and a device with alarms, illumination or another pulsed load may not place the same demand on the cell.

When the removed battery carries a complete code such as SR626SW, record the suffix. Do not shorten it to SR626 in the lookup process. If the device specifies a paired number such as 377/376 or 357/303, check which version the manufacturer recommends for that application.

LR44, AG13, A76 and 357 are not one chemistry

LR44, AG13 and A76 are common labels associated with an alkaline button-cell size family. The 357/303 family is normally silver oxide. They can be physically similar, and replacement charts may list overlapping size references, but their chemistry and discharge characteristics differ.

A retailer should not say that every LR44 and 357 is "the same battery". The correct explanation is that some labels refer to cells with similar dimensions, while the appropriate replacement depends on the specified voltage, chemistry and load. Where a device manufacturer specifies silver oxide, an alkaline substitute may give a different operating life or voltage curve even if it fits.

Use a seven-point equivalence check

1. Original code: copy every letter, digit, slash and suffix from the removed cell or device instructions.
2. Chemistry: identify CR, SR, LR or another specified chemistry.
3. Nominal voltage: match the device requirement.
4. Dimensions: confirm diameter, thickness and any special case profile.
5. Terminal arrangement: check positive and negative faces, tabs or special contacts.
6. Load class: preserve high-drain or low-drain information where applicable.
7. Manufacturer evidence: use a current replacement chart or device manual to confirm the final selection.

If one of these fields is unknown, the safe response is to pause the sale and ask for the device model or technical reference. Guessing from a photograph or measuring only the diameter is not enough.

Avoid common miniature-battery mistakes

• Dropping a suffix: CR2450N, SR626SW and SR920W contain information that may affect fit or performance.
• Using diameter alone: CR2016, CR2025 and CR2032 share a nominal diameter but have different thicknesses.
• Equating physical fit with electrical suitability: an alkaline and silver-oxide cell can look similar but behave differently.
• Stacking cells: never combine cells to imitate the size or voltage of another battery unless the product was designed and instructed for that arrangement.
• Recharging a primary cell: do not recharge a battery unless it is specifically marked rechargeable and the correct charger is used.
• Mixing old and new cells: replace sets as the device manufacturer instructs and do not mix chemistries or brands in one device.
• Reversing polarity: follow the positive and negative markings in the product.
• Handling with metal objects: loose cells can short-circuit against coins, keys, tools or other batteries.

Build a searchable variant record

A single Shopify product can contain many battery-code variants. Each variant needs enough information to be ordered, picked and scanned correctly. Recommended fields include:

• display code, including suffix;
• manufacturer and manufacturer part number;
• chemistry and nominal voltage;
• diameter and thickness from the data sheet;
• recognised cross-reference terms;
• retail pack quantity and trade pack quantity;
• variant SKU and barcode;
• batch or date code where supplied;
• stock location; and
• supplier and last verification date.

Keep synonyms in search fields, not by replacing the official variant name. For example, a listing can make "377" and "SR626SW" searchable while retaining the stocked manufacturer's exact label. This reduces duplicate SKUs and helps staff find the right line from either code.

Plan the range around code coverage

Miniature batteries create a long-tail assortment: a small number of common codes may move regularly, while specialist sizes sell less often but matter when a customer needs an exact replacement. Measure performance by individual variant, not only by the parent product.

A practical range review can separate:

• core coin cells such as CR2016, CR2025 and CR2032;
• regular watch-number families such as 364, 371 and 377;
• specialist watch codes justified by local repair or jewellery demand;
• key-fob, calculator, remote and alarm formats; and
• codes with repeated customer requests but no current stock.

Track units sold, weeks of cover, stockouts, returns caused by wrong codes and age of the oldest pack. Do not remove a technically necessary variant solely because the parent product appears slow; the decision should use the code-level record.

Rotate stock and protect the packaging

Follow the manufacturer's storage conditions. Keep batteries cool, dry and away from direct sunlight, heat and moisture. Use first-in, first-out rotation by batch or delivery date, and do not sell packs with corrosion, leakage, swelling, torn child-resistant features or unreadable codes.

Do not tip different codes into a common loose container. Original packaging helps prevent short circuits, preserves warnings and keeps the product identifiable. Returned or waste cells should have exposed terminals protected as the collection scheme instructs and be stored in a suitable container away from stock offered for sale.

Treat ingestion risk as a point-of-sale safety issue

Button and coin batteries can cause severe internal injury if swallowed or inserted, particularly by children. The Office for Product Safety and Standards business guidance encourages manufacturers, importers and distributors to follow PAS 7055:2025 where more specific product standards do not apply.

For distributors, the guidance recommends checking secure battery compartments in products and considering prominent warnings on packaging, at the physical point of sale and in online product descriptions or images. For batteries sold separately, retain the manufacturer's protective packaging and hazard warnings. Do not place loose miniature cells where children can handle them.

If ingestion is suspected, it is a medical emergency. Staff should direct the person to emergency medical help immediately and should not advise waiting for symptoms or attempting a home remedy.

Keep traceability for safety and recalls

Under the General Product Safety Regulations guidance, distributors must act with due care, should retain supplier traceability and must cooperate with corrective action or recalls. A goods-in record can capture supplier, invoice, manufacturer, code, barcode, batch, quantity and packaging condition.

Quarantine any cell or pack that does not match the ordered code, lacks essential warnings, appears counterfeit, is damaged or has been affected by a recall. Because several cells look alike, identify recall stock by exact model, barcode and batch rather than colour or diameter.

Apply the 32kg battery-takeback rule where required

The government's battery-waste guidance says a retailer or distributor selling or supplying 32kg or more of portable batteries per year must offer free collection of waste batteries. The takeback duty includes portable batteries used in watches, hearing aids, mobile phones, cameras, torches and many other products.

A qualifying retailer must provide a suitable collection point, tell customers about it and arrange compliant recycling through a battery compliance scheme. The collection is not limited to the exact battery brands sold by the shop. Smaller sellers below the threshold can offer voluntary takeback, but they must still arrange lawful storage, collection and transport.

Used miniature cells can retain enough energy to cause harm or short-circuit. Keep the takeback container away from children, metal objects and combustible waste, and follow the scheme's terminal-protection and storage instructions.

Use a consistent counter lookup

1. Ask for the device instructions or exact code from the old battery.
2. Copy the complete code, including W, SW, N or paired-number suffixes.
3. Check chemistry and nominal voltage.
4. Confirm dimensions and any special terminal profile.
5. Use the stocked manufacturer's current cross-reference chart.
6. Match the sealed retail pack, SKU and barcode.
7. If the evidence conflicts or remains incomplete, do not guess.

The broader wholesale-battery guide range also contains AA, AAA, C, D, 9V, rechargeable and specialist formats. Keep miniature-cell lookup separate from those household size groups so staff do not use a generic battery category as proof of compatibility.

Retailer checklist for button, coin and watch batteries

• Preserve the complete manufacturer code and suffix.
• Record chemistry, voltage and dimensions separately.
• Use current manufacturer cross-reference evidence.
• Make both short numbers and IEC-style codes searchable.
• Keep retail-pack and trade-pack quantities distinct.
• Rotate by batch or delivery date and protect original packaging.
• Display ingestion warnings and keep loose cells inaccessible.
• Retain supplier and batch traceability.
• Quarantine damaged, leaking, suspect or recalled stock.
• Review the 32kg takeback threshold and collection duties.

Frequently asked questions

Are CR2032, CR2025 and CR2016 interchangeable?

No. They share a nominal 20mm diameter but have different thicknesses and capacities. Use the code specified by the device manufacturer.

Is LR44 the same as 357?

They can belong to a similar physical-size family, but LR44 is alkaline while 357/303 is normally silver oxide. The correct replacement depends on the device's specified chemistry and load.

What does SR626SW mean?

It identifies a round silver-oxide watch-cell family with a specific size and drain classification. Manufacturer charts commonly cross-reference it with the 377/376 number family, but the original device requirement should be checked.

Can a CR2450 replace CR2450N?

Not automatically. The suffix can indicate a different case or contact profile. Use the device manual and manufacturer data for the exact code.

Can dead button batteries be kept loose for recycling?

No. Used cells can retain charge and short-circuit. Follow the collection scheme's instructions for terminal protection and suitable storage, away from children and metal objects.

When must a retailer offer free waste-battery takeback?

The mandatory threshold is 32kg or more of portable batteries sold or supplied per year. Qualifying retailers must provide a suitable collection point and tell customers about it.