Onto vs. On to: What’s the Difference?

It can be tough sometimes to remember the difference between onto and on to. They look almost the same written on paper, separated by just one little space. Plus, when you say them out loud, they sound almost indistinguishable. But even though you may skip right over them in casual conversation, these words have subtle differences that are very important to remember when you are writing.

What is the Difference Between Onto and On to?

So, is onto a preposition or an adverb? The sense of the sentence should be able to tell you, but it still can be tricky. Today, I want to go over onto vs. on to and give you a few tips to remember their difference.

When to Use Onto

Onto is a preposition that means, on top of, to a position on, upon. Onto implies movement, so it has an adverbial flavor to it even though it is a preposition. For example,

• The cat jumped onto the dresser.
• The gymnast jumped onto the mat.

In both of these sentences, onto is acting as a preposition and takes the objects dresser and mat.

Onto also has an informal prepositional meaning of to be fully aware of, informed about. For example,

• I’m onto you and your dirty tricks.
• The police are onto the robbers.

Again, the preposition onto takes the objects you and robbers in these two sentences.

When to Use On to

Use on to, two words, when on is part of a verb phrase. In instances when on is part of the verb, it is acting as an adverb and to is the preposition, which takes an object. For example,

• I will log on to the computer.
• She held on to the chains while swinging.

Both of these sentences have verb phrases, log on and held on. And in both cases, to takes a preposition, the computer and the chains.

Remember the Difference

A good trick to remember on to vs. onto is to mentally say “up” before on in a sentence. If it still makes sense, then onto is probably the correct choice. For example,

• The cat jumped up onto the dresser. (CORRECT)
• I will log up on the computer. (WRONG)

Practice Quiz and Examples

1. Be sure to hang ______ the handlebars.
2. If you climb ______ that beam, you might get hurt.
3. After visiting the space museum, we moved ______ the aquarium.
4. To get a better view, we went ______ the ridge.

Display the answers below

Confusion

Both onto and on can be used to indicate motion toward a position. For example,

• The dog jumped onto the couch.
• The dog jumped on the couch.

Both of these sentences show the motion of the dog arriving on the couch, but the words communicate slightly different things.

Onto is more specific than on because it indicates that the motion was initiated from an outside point. For example,

• The group wandered onto the basketball courts.
• The group wandered on the basketball courts.

The first sentence means that the group was wondering somewhere off the court and then they found it. The second sentence implies that the wandering actually began on the court and that the group never left.

Furthermore, even though on can also imply motion, it doesn’t always. For example,

• She is good on piano.
• He is good on the basketball court.

Neither of these sentences has anything to do with motion.

Summary

Onto is a preposition, it implies movement, and is more specific that on.

On to are two words, and when paired with each other, on acts as a part of a verbal phrase and to acts as a preposition.

You can quickly remember the different by saying “up” before on/onto.

Answers

1. On to
2. Onto
3. On to
4. Onto