I spent $500 for/on her treatment.

[sweetie_sneha]

Dear Teacher,

Which of the following is correct?

I spent $500 for her treatment.

or

I spent $500 on her treatment.

[Tdol]

They're both OK.

[asad hussain]

I would better use "on" here.

[MikeNewYork]

Dear Teacher,

Which of the following is correct?

I spent $500 for her treatment.

or

I spent $500 on her treatment.

I agree with Tdol. Both are OK and very common.

[curmudgeon]

You might say 'I gave her $500 for her treatment.

[jcanody]

Is the treatment continuing? If so, I would use "on".

If the treatment is complete, I would use "for".

Though this is probably not a necessary distinction, it seems a matter of intent to me.

[MikeNewYork]

You might say 'I gave her $500 for her treatment.

That would have a different meaning for me. Your version suggests that the money was given to the woman; the other implies that the money was given to the provider.

[curmudgeon]

Ok then 'I gave $500 towards her treatment