Should I buy a 58mm or an 80mm thermal printer?
Buy 80mm for a counter that prints full GST bills, and 58mm when the printer has to be small, light or run from a phone. If you are unsure and have a fixed counter, 80mm is the safer choice.
| 58mm (2 inch) | 80mm (3 inch) | |
|---|---|---|
| Characters per line (Epson TM-T82IV, Font A) | 35 | 48 |
| Best for | Phone billing, delivery, small counters, few items per bill | Fixed counters, many items per bill, GST bills with HSN |
| Long item names and tax columns | Wrap onto two lines more often | Usually fit on one line |
| Typical connection | Bluetooth, often battery-powered | USB, LAN (network) or Wi-Fi; some Bluetooth |
| Bill length | Longer for the same bill | Shorter for the same bill |
| Paper rolls | Easy to find | Easy to find |
Characters per line from Epson's TM-T82IV specification; other models differ, so read the column count on the spec sheet before buying.
What else to check before you buy
- Auto-cutter: on a busy counter, a printer that cuts the bill itself saves time and torn bills. Check the spec sheet for "auto-cutter"; many portable 58mm printers only have a tear bar.
- Driver and app support: the printer must work with your computer (Windows driver) or with your billing app on the phone.
- Service near you: a printer brand with a service centre or dealer in your city is worth more than a small saving on price.
- Cash drawer port: if you use a cash drawer, pick a printer that can open it after each bill.
Will a 58mm bill fit GST details and HSN?
Yes, a 58mm bill can carry every field Rule 46 asks for, but it gets long and item names wrap. With fewer than about 35 characters a line, a line with item name, HSN, quantity, rate, GST and amount usually takes two lines.
Rule 46 asks for the supplier's GSTIN, a serial number, date, HSN code, description, quantity, taxable value, tax rate and tax amount, plus the buyer's details in some cases. If your turnover is up to ₹5 crore, Notification 78/2020 lets you leave the HSN off bills to unregistered buyers, which saves space on 58mm. A good billing app puts the GST break-up in a small table at the bottom instead of on every line. Compare layouts on our GST invoice format page, which has an 80 mm thermal sample.
Bluetooth, USB or LAN: which for a phone and which for a PC?
Use Bluetooth (or Wi-Fi) for a phone or tablet, and USB or LAN for a computer. A LAN (network) printer also lets two counters share one printer.
| Connection | Works with | Good to know |
|---|---|---|
| Bluetooth | Phones and tablets | Pair once; keep the printer charged if it runs on battery |
| USB | Windows PC or laptop | Simple and reliable; needs the printer driver installed |
| LAN / Ethernet | PCs and phones on the shop network | Give it a fixed IP so it is not lost after a router restart |
| Wi-Fi | Phones and PCs on the same Wi-Fi | Convenient, but depends on a steady Wi-Fi signal |
Before buying, confirm that your billing software prints over that connection. Browser-based software prints through the computer's printer driver; a phone app prints over Bluetooth or the network.
How long does thermal print last for GST record keeping?
Thermal print fades with heat, light and time, and GST records must be kept for 72 months from the due date of the annual return. So do not rely on the paper slip as your record; keep the bill in your software or as a PDF.
Paper makers quote different image lives for different grades, so read the label on the roll box if you need a number. Store any slips you keep away from sunlight, heat and plastic sleeves. The customer's copy can fade; your record is the bill saved in the software, which you can reprint or send on WhatsApp any time.
What is the paper roll cost per month?
It depends on how many bills you print and how long each one is, so work it out from your own numbers rather than a quoted figure. Rolls are sold by width and length in metres, and prices change often.
- Measure one bill Print a typical bill and measure its length in centimetres.
- Count bills per day Take an average day from your sales report.
- Work out metres per month Bill length × bills per day × days open ÷ 100.
- Divide by roll length Read the length on the roll box; that gives rolls per month.
- Check current price Multiply by the current price per roll from your stationery supplier.
Sending bills on WhatsApp instead of printing for customers who do not want paper cuts this cost; see sending bills on WhatsApp.
Can I print A4 and thermal from the same software?
Yes, most billing software lets you choose the bill format: thermal for walk-in customers and A4 for business buyers who want a full-page tax invoice. Check that you can pick the format per bill, not only once in settings.
Many shops keep an 80mm thermal printer at the counter and print A4 only for B2B bills or quotations. Read thermal printer vs A4 invoice for when each is better.
Why is my thermal print blank or faded?
A completely blank bill almost always means the roll is in the wrong way round; thermal paper prints on one side only. Faded print usually means low print density, a dirty print head, a weak battery or poor paper.
- Scratch the paper with a fingernail: the side that turns dark must face the print head
- Raise the print density or darkness in the printer settings or driver
- Clean the print head with a soft cloth and isopropyl alcohol when the printer is off and cool
- Charge a Bluetooth printer fully; low battery gives light print
- Try a roll from a different supplier
- Check the paper width setting in the billing software matches the roll (58 or 80)