Do snap-on cup lids fit and stay on?

Lids fit the rim, not the ounces

A lid snaps over the rolled rim at the top of the cup. What matters is the width and the shape of that rim. The number of ounces on the box tells you how much the cup holds, not how wide its top is.

This is why a "16 oz lid" from one maker can be loose on a "16 oz cup" from another maker. It is also why one lid can fit more than one size: some makers use the same rim on cups of several sizes and change only the height. You cannot know this from the ounces.

To get a lid that fits:

Buy cups and lids made as a set. This is the safest way. The maker made the lid for that rim.
If you buy lids apart from the cups, buy them from the same maker and the same cup line, and check that the lid's listing names your cup.
Do not mix lids from a different cup line without testing one first. A lid that looks the same can be a little too wide or too narrow.

Oojami cups come with their lids: 100 cups and 100 matching lids in every pack. Each size comes with lids for that size.

Do snap-on lids stay on when you walk?

A snap-on lid stays on when it is pressed down all the way round the rim. Many lids click when they lock. If one part of the edge is not down, a small bump or a squeeze can push the lid off.

The Oojami lid snaps onto the rim and stays on while you walk or set the cup down. A flap on the lid opens for sipping and closes again to cut splashes.

Why lids drip, and how to stop it

A sip lid has an opening, so it is not a seal. Most drips come from one of these causes:

Cause	What happens	What to do
The lid is not fully snapped on	A gap stays open at one part of the rim, and drink comes out there	Press round the full edge with your thumb until it locks all the way round
The cup is squeezed	A thin cup bends, the rim goes out of round, and the lid lifts	Hold the cup lower down, without a tight grip. A rigid cup bends less
The cup is tipped or on its side	Drink comes out of the sip opening	Keep the cup upright. Close the flap if the lid has one
The cup is filled to the top	Drink hits the lid when you walk and comes out of the opening	Leave some space at the top under the lid
The lid is from a different cup line	The lid is a little too wide and does not grip	Use the lids made for the cup
Water drops on the outside	A cold drink makes water collect on the outside of the cup. This is not a leak	Use a napkin or a cup sleeve

Are sip lids leakproof?

No. A sip lid resists spills: it keeps most of the drink in when the cup moves or gets a small bump. It does not seal. If the cup falls on its side, drink comes out of the opening. Any cup with a sip opening or a straw hole can do this, from any maker.

If you need a drink that cannot spill in a bag or on a car seat, use a travel tumbler with a lid that screws on and has a seal. A disposable cup is for a drink you hold upright or keep in a cup holder.

Cups with lids included: what to look for

The lid is made for the cup. A set from one maker, with one lid for each cup.
The cup is rigid. A cup that keeps its shape when you hold it keeps the rim round, so the lid stays on. Oojami cups are PET, which keeps its shape under ice and a full pour.
The lid type suits the drink. A sip lid for thin drinks, a straw lid for thick drinks, a dome lid for toppings.
The lid closes. A flap or a plug on the opening cuts splashes when you carry the cup.

Oojami cups are for cold drinks only. They are BPA-free and recyclable.

Other choices

Solo UltraClear, GUSTO and Great Value also sell clear cold cups with lids for the same cups. Use the lids sold for the cup you have.
A reusable travel tumbler with a screw-on lid is the better buy if you need a drink that does not spill when it falls over.