I can't get ahold of him.

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hi,

What is the difference between:

“I can’t get ahold of him” and “I can’t get hold of him”?

Many thanks,
Cantik

2

See this: idioms.thefreedictionary.com/get+ahold+of

Get a hold of someone - reach them, contact them, communicate with them

Get hold of someone (also from the free dictionary)
get hold of:

  1. To come into possession of; find: Where can I get hold of a copy?
  2. To communicate with, as by telephone: tried to get hold of you but the line was busy.
  3. To gain control of. Often used reflexively: You must get hold of yourself!

You can see that #2 means the same as “get ahold of” but it also has other meanings.