The chords are the same for every part of the song. 
I have written the chords on the verse and chorus so you can get a hint on the rythm.

Intro

Ab

Heaven only knows
Heaven only knows

C#maj7    Bbm7    C7           Fm7  Em7  Ebm7  Ab7          C#maj7

Yeah              Heaven only knows       Oh    Heaven Only knows

Bbm7    C7            Fm7  Em7    Ebm7   Ab7

 Oh     Heaven only knows         Yeah

(This is also the same structure as the chorus. Use it for reference)


C#maj7
Last night was the worst night

Bbm7             C7

Beginning of the end

   Fm7                  Em7 Ebm7        Ab7

Or maybe it began before it here we go again            Verse(s)

C#maj7

Things got so dramatic

Bbm7              C7

Things got out of hand

Fm7                             Em7

We said words we couldn't imagine

Ebm7             Ab7

I don't understand


C#maj7                 Bbm7     C7

There you go with the same old thing

      Fm7            Em7  Ebm7                Ab7

When things go wrong you always seem to blame me

C#maj7                         Bbm7                C7

Now I would like to find what secrets hide in your mind

Fm7

Where the end will go

Em7    Ebm7       Ab7            C#maj7

Will I ever know heaven only knows

Heaven only knows
Heaven only knows
Heaven only knows
Heaven only knows

Make this night the best night
It's time for second chance
Turn the beat up on repeat and we can start to dance
Sometimes when we talking words
Drowned on by the sound

Let's get back to touching, we'll get back on solid ground
Let's hold hands
Like the young romance
Let's first kiss like the moment we first did
Can we make love
Like way back in the day?
We can lose control, baby don't say "no"

Heaven only knows
Heaven only knows
Heaven only knows
Heaven only knows

Will you come back to me?
Heaven only knows
Will you come back to me?

Make this night the best night
It's time for second chance
Turn the beat up on repeat and we could start to dance

Heaven only knows
Heaven only knows
Heaven only knows



Updates:

Fixed chord positions