What do the marks on a glass bottle mean? They’re the key to helping you read a glass bottle or jar and learning about where it was produced and which glass company crafted it.

The next time you pick up your favorite glass bottle of beer, spirits, or even foods like salsa and ketchup, take a closer look at the heel and the base of the glass container. Run your fingers along it too. You’ll find a series of symbols, letters and numbers. Those numbers, letters and symbols – also called a bottle code — are the clues about where that glass container was made.

How to Read a Glass Bottle

O-I Glass has more than 70 glass making plants globally. Here is how you decipher the bottle code on an O-I glass bottle or jar:

Region, Plant Identification

Wonder where your bottle was made? This letter and number combination shows which O-I manufacturing plant made your bottle

Region Codes:

A – Asia Pacific

E – Europe

N – North America

S – South American

O-I Bottle Manufacturing Mark

This shows you if a bottle was indeed made by O-I or another glass packaging manufacturer

Cavity Identification

Our glass containers pass rigorous inspections before they’re sent to customers. The Braille-like bumps on the heel and/or rings on the bottom are the cavity identification and enable our inspection equipment to read the bottle identification information

Two digit number

The year the bottle was manufactured

Mould Equipment Identification Number

A mould is a hollow metal part on our bottle making machines used to form the shape of each bottle. You’ll find this number on the base.

While coding can vary by region or customer, these general rules will help you read a glass bottle. Give it a try the next time you have one in your hand – maybe it’s even your new party trick.

At O-I, we’ve been making glass containers for communities around the world for more than 100 years. We love glass for its sustainable benefits as well as its simple nature. Not only is it 100% recyclable and infinitely recyclable, but it’s made from natural raw materials that make it the kindest packaging material for the planet and for people.