Ream of Paper: How Many Sheets, What gsm Means and How Long It Lasts

A ream of paper is 500 sheets. When you buy an A4 paper ream for a printer or copier in the UK, you are buying 500 sheets of 210 x 297mm paper in one wrapped pack, and the gsm number on the wrapper tells you how heavy the paper is.

This guide explains what a ream is and why paper is sold that way, what gsm tells you about weight and feel, and how to work out how long a ream will last in your office or packing room using your own numbers. It then matches paper to the jobs a small business prints every day: invoices, packing slips, customer letters and labels. The last section covers how many reams to buy and what they cost.

Quick picks for office and packing room printing

These three cover the paperwork that goes with most orders: the sheet you print on, the labels you stick on and the wallet that holds the invoice.

Best for invoices and packing slips

A4 Printing Paper (500 Sheets per Ream)

White A4 paper for printers and copiers, sold by the ream of 500 sheets.

• 500 sheets per ream, A4 (210 x 297mm)
• Standard 75gsm or Paper One Premium 80gsm
• Sold by the single ream, with volume pricing

From £6.50 ex VAT (£7.80 inc VAT)

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Best for address and product labels

A4 Sheet Labels

Self-adhesive labels on A4 sheets that go through the same office printer as your paper.

• 10 layouts, from 1 to 65 labels per sheet
• Boxes of 500 sheets
• Label sizes from 199.6 x 289.1mm down to 38.1 x 21.2mm

From £30.00 ex VAT (£36.00 inc VAT)

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Best for invoices on the outside of a parcel

Documents Enclosed Wallets

Clear self-adhesive pouches that hold the invoice or packing list on the box.

• A5 (225 x 165mm), A6 (158 x 110mm) and A7 (95 x 125mm)
• Plain or printed Documents Enclosed
• Boxes of 1000 wallets

From £15.00 ex VAT (£18.00 inc VAT)

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What is a ream of paper and how many sheets are in it?

A ream of paper is a pack of 500 sheets of the same size and weight. It is the standard unit for buying printer and copier paper, so when a listing says A4 paper 500 sheets, it means one ream.

The ream is a counting unit, the same way a dozen is. It says nothing about the size of the sheet or how heavy the paper is. Those are printed separately on the wrapper: the size (A4, which is 210 x 297mm) and the weight in gsm. A ream of A4 at 75gsm and a ream of A4 at 80gsm both hold 500 sheets. The 80gsm ream is a little heavier to pick up.

Our A4 printing paper is sold this way. Each ream holds 500 white A4 sheets, and you choose between Standard 75gsm and Paper One Premium 80gsm. You can order a single ream. If you want the sheet dimensions in every unit, plus the envelopes that take A4 flat or folded, our guide to A4 paper size in cm, mm and inches has them.

How many reams come in a box depends on the brand and the supplier, so check the listing before you order paper by the box. We sell our paper by the ream, and you choose how many reams you want.

What does gsm mean on an A4 paper ream?

The gsm figure is the weight of the paper in grams per square metre. A higher number means a heavier sheet, which usually feels a little thicker and stiffer in the hand.

You can turn gsm into a real weight with one sum. An A4 sheet is one sixteenth of a square metre, because sixteen A4 sheets tile an A0 sheet and A0 is one square metre. So one sheet of 80gsm A4 weighs 80 divided by 16, which is 5 grams. One sheet of 75gsm weighs about 4.7 grams.

Those figures are for the paper only and leave out the wrapper. They are useful if you carry paper up stairs, or if you post documents and want a rough idea of what ten printed pages add to a parcel: about 50 grams at 80gsm.

Weight and thickness are related but they are different measurements. Two papers with the same gsm can differ slightly in thickness depending on how they are made, which is why we do not quote a thickness for a sheet or a ream here. In use, 80gsm feels a touch heavier than 75gsm, and the difference of 5gsm is small. Most people holding one sheet of each can only just tell them apart.

Heavier grades such as 90gsm and 100gsm exist for letterheads and presentation documents. We stock 75gsm and 80gsm only. If you are weighing up the heavier grades, our A4 paper guide comparing 80gsm, 90gsm and 100gsm goes through them in detail.

How long does a ream of paper last in a small office or packing room?

A ream lasts 500 divided by the number of sheets you print in a day. There is no useful average to quote, because a one-person online shop and a ten-desk office print very different amounts. Use your own numbers.

In a packing room the daily total follows the number of orders you send, so work it out in this order.

1. Count the sheets per order. Look at what goes in or on one parcel: a packing slip, an invoice, a returns form, a courier label printed on plain paper. Add up the A4 sheets.
2. Multiply by your orders per day. Use a normal day, then do the sum again for your busiest day.
3. Add the office printing. Picking lists, purchase orders, letters and anything else that comes off the same printer. A week of counting the sheets you load gives you this figure.
4. Divide 500 by the daily total. The answer is how many working days one ream lasts.
5. Add a margin for waste. Misprints, jams and test pages use paper too. Keep one unopened ream on the shelf so a bad day does not stop dispatch.

The table below runs the arithmetic for a few made-up workloads. They are examples of the method, so swap in your own figures.

So a seller sending 25 orders a day with one A4 packing slip in each uses a ream every 20 working days. Add a separate invoice to each order and the same seller uses a ream every 10 days. That second sheet doubles the paper bill, which is why it is worth asking whether you need it.

To get the cost per sheet, divide the ream price by 500. At our starting price of £6.50 ex VAT, a sheet costs 1.3p before VAT. Ink or toner usually costs more than the paper it goes on. That is one reason busy dispatch desks move their courier labels onto thermal printers, which use no ink at all.

Which paper should you buy for invoices and packing slips?

For packing slips, picking lists and internal copies, Standard 75gsm does the job. For invoices, quotes and letters that a customer will handle, Paper One Premium 80gsm feels slightly heavier. Both are white A4 and both run through any printer or copier set to A4.

Best for everyday business printing

A4 Printing Paper (500 Sheets per Ream)

One product, two weights: pick 75gsm for volume and 80gsm for documents customers see.

• Standard 75gsm: packing slips, picking lists, drafts
• Paper One Premium 80gsm: letters, quotes, reports
• Ream of 500 A4 sheets (210 x 297mm)

From £6.50 ex VAT (£7.80 inc VAT)

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Reams run from £6.50 to £8.50 ex VAT (£7.80 to £10.20 inc VAT) depending on the type you choose, and the price per ream falls as you order more. The tiers are shown on the product page.

We would split the print jobs between the two weights like this.

Plenty of businesses keep both: 75gsm by the dispatch printer and 80gsm in the office copier. If that sounds like more stock than you want to manage, buy one grade and use it for everything. A customer is unlikely to notice a 75gsm invoice, and nothing goes wrong if you print a picking list on 80gsm. The only cost is the price gap between the two reams.

Once the invoice is printed, it has to travel with the parcel. A documents enclosed wallet is a clear self-adhesive pouch that sticks to the outside of the box or mailing bag, so the paperwork can be read without opening the parcel. An A4 invoice folded once (148 x 210mm) fits the A5 wallet, which is 225 x 165mm. Folded twice (105 x 148mm), it fits the A6 wallet at 158 x 110mm. There is also an A7 wallet at 95 x 125mm for small slips. Wallets come plain or printed with the words Documents Enclosed, in boxes of 1000, from £15.00 ex VAT (£18.00 inc VAT). Our documents enclosed wallets guide covers sizes and when to choose plain or printed.

You do not always need a wallet. If the parcel is going to a consumer and the slip is only for them, fold it and put it inside the box on top of the goods. A wallet is worth using when a courier, a goods-in desk or customs needs to read the paperwork from the outside.

Should you print labels on plain A4 paper or on A4 label sheets?

Use plain paper if you are happy to cut the label out and tape it on, and use A4 label sheets if you want to peel and stick. Plain paper is the cheaper sheet. Label sheets save the scissors and the tape, and they stay flat on the parcel.

Our A4 sheet labels are self-adhesive labels on standard A4 sheets, made for an office printer. They come in boxes of 500 sheets, the same count as a ream of paper, so the sum from the last section works here too. There are 10 layouts, and the layout decides how many labels you get from a box.

A box of A4 sheet labels is £30.00 ex VAT (£36.00 inc VAT) in every layout. For matching a layout to your software template and getting the print to line up, see our guide to address labels on A4 sheets.

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If you print courier labels all day, there is a third option: a thermal printer with thermal labels on rolls, which uses no ink, toner or ribbon. Rolls come in five sizes including the standard 4 x 6" (100 x 150mm) courier label, from £3.50 ex VAT (£4.20 inc VAT). We sell the labels but we do not sell label printers, so you would need to buy the printer elsewhere. Our comparison of thermal rolls, fanfold and A4 sheets helps you decide whether the switch is worth it at your volume. You can see every type in the labels collection.

How should you store and load a ream of paper?

Keep reams wrapped, flat and dry until you need them, and load only as much as the tray is marked to take. Paper takes up moisture from the air, and damp or curled sheets are a common cause of jams and misfeeds.

1. Leave the wrapper on. Open a ream when you are about to load it. If you use half, fold the wrapper back over the rest.
2. Store reams flat. Stack them on a shelf, not on a concrete floor and not standing on edge, which bends the sheets.
3. Keep paper away from doors and heaters. A packing room with a roller shutter open all day is harder on paper than an office. A cupboard or a lidded box is enough.
4. Fan the stack before loading. Flick through the edge of the stack to separate the sheets, then square it up on the desk.
5. Fill to the tray line. Most trays have a maximum fill mark. Overfilling causes double feeds. Check your printer manual for the tray capacity.
6. Use the oldest ream first. Put new stock at the back of the shelf so nothing sits for a year.

If you buy several reams at once, store them in a plain cardboard box with the flaps closed, which keeps dust and damp off them. Our guide to cardboard storage boxes covers choosing and labelling boxes for the shelf. Write the gsm on the outside so nobody loads the wrong grade.

Paper is only one of the things a dispatch area needs. If you are setting one up from scratch, our rundown of shipping supplies for a packing bench lists the tools and consumables that sit alongside the printer.

How many reams should you buy, and what does a ream cost?

Buy enough reams to cover about a month of printing, plus one spare. That keeps the price per ream down through volume pricing without filling a shelf with paper that could get damp before you use it.

Our A4 printing paper starts from £6.50 ex VAT (£7.80 inc VAT) per ream of 500 sheets, and you can order one ream at a time. The price per ream falls as the quantity goes up, and the tiers are shown on the product page. Use the table in the section on how long a ream lasts to turn your daily sheet count into a monthly number of reams, then check which price tier that number lands in. If you are one or two reams short of the next tier, it can be worth rounding up, as long as you have dry storage.

• Delivery. Royal Mail Tracked 48 is free on every order with no minimum, so a single ream costs nothing extra to send.
• Same-day dispatch. Orders placed by 2pm Monday to Friday leave our Manchester unit the same working day.
• Collection. Click and collect from Cheetham Hill is free and usually ready within 2 hours.
• Local van delivery. If you are within 10 miles of Cheetham Hill, see same-day local delivery in Manchester.
• Regular orders. A trade account suits businesses that reorder paper, labels and packaging every month. A VAT invoice comes with every order.

You can order paper with the rest of your packaging. If you are already buying mailing bags or boxes, add the reams, label sheets and wallets to the same basket and they arrive together. For paper across several sites, or a quantity beyond the tiers shown, phone 0161 706 1246 or use the contact page.

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Frequently Asked Questions

How many sheets are in a ream of paper?

A ream of paper holds 500 sheets. That count is the same whatever the paper size or weight, so a ream of A4 at 75gsm and a ream of A4 at 80gsm both contain 500 sheets. Pack Solution sells A4 printing paper by the ream of 500 sheets.

How many reams of paper are in a box?

The number of reams in a box of paper varies by brand and supplier, so check the listing before you buy paper by the box. Pack Solution sells A4 printing paper by the ream, and you choose how many reams to order. The price per ream falls as the number of reams goes up.

What is the difference between 75gsm and 80gsm A4 paper?

80gsm A4 paper is slightly heavier than 75gsm A4 paper. The gsm figure is grams per square metre, so one A4 sheet of 80gsm weighs 5 grams and one A4 sheet of 75gsm weighs about 4.7 grams. Use 75gsm paper for packing slips and internal copies, and 80gsm paper for invoices and letters that customers keep.

How much does a ream of A4 paper weigh?

A ream of 80gsm A4 paper weighs about 2.5kg, and a ream of 75gsm A4 paper weighs about 2.3kg, not counting the wrapper. The sum is the gsm divided by 16 to get the weight of one A4 sheet in grams, multiplied by 500 sheets.

How long does a ream of paper last?

A ream of paper lasts 500 divided by the number of sheets you print each day. A packing room printing 25 sheets a day uses one ream in 20 working days, and one printing 100 sheets a day uses a ream in 5 days. Count the sheets you load for a week to find your own daily figure.

Can you print labels on a normal ream of A4 printer paper?

You can print a label on normal A4 printer paper, but plain paper has no adhesive, so the label has to be cut out and taped to the parcel. A4 sheet labels are self-adhesive and peel off the backing sheet. Pack Solution sells A4 sheet labels in 10 layouts, from 1 to 65 labels per sheet, in boxes of 500 sheets.

Shop for This Job

• Labels
• Cardboard Boxes
• Mailing & Polythene Bags

Related Guides

• A4 Paper Guide: 80gsm, 90gsm and 100gsm Compared
• A4 Paper Size in cm, mm and Inches, Plus the Envelopes That Fit A4
• Address Labels on A4 Sheets: Sizes, Layouts and Printing Tips

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