1 B1 neutral
To formally agree to join or participate in a specific agreement, plan, or project.
"Several countries have signed onto the new climate agreement."
inseparable
sign onto
B1 neutral inseparable transitive
To formally agree to join or participate in a specific project, agreement, or system.
In plain English
To officially agree to be part of a specific thing, like a plan or a team.
What does "sign onto" mean?
2 meanings, ordered from most common to least. Color-coded by CEFR level.
2 A2 neutral
To log in to a specific digital system or platform.
"You'll need to sign onto the company portal to submit your timesheet."
inseparable
Usage tip
Slightly more formal than 'sign up for'. Often used in professional or political contexts when someone joins a specific initiative, treaty, or agreement. Also used in digital contexts to mean 'log in to a specific system'.
Words that pair with "sign onto"
Natural word combinations native speakers use most often.
agreement treaty project platform deal initiative
How to conjugate "sign onto"
The five tense forms you'll use most often.
Base
sign onto
I/you/we/they
3rd person
signs onto
he/she/it
Past simple
signed onto
yesterday
Past participle
signed onto
have + pp
-ing form
signing onto
continuous
Hear "sign onto" in the wild
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