accomplish / fill up a form

[epistolario]

Here, the verb accomplish and the phrasal verb fill up have developed an extended meaning. Both of these are used with forms:

You need to accomplish the application form.
I didn't fill up the survey form.

Have you encountered this particular usage of these words to mean fill out or fill in or complete?

You need to completely fill out the online application form.
I didn't complete the survey form because it's a waste of time.
I forgot to fill in the withdrawal slip before I went to the teller.

In addition, I normally hear fill in the blanks. Do you also say fill out the blanks when you are talking to the examinees?

 

[heypresto]

You need to accomplish the application form.
I didn't fill up the survey form.

Have you encountered this particular usage of these words to mean fill out or fill in or complete?

No.

 

[Cenzontle]

Like heypresto, I have not heard "accomplish" or "fill up" used in that way.
When you "fill out" a form, you complete it, filling all the blanks.
The "out" emphasizes completion.
But you would not normally "fill out" a single blank. You would just write the required information (filling in the blank),
regardless of whether it truly filled the entire blank.