G        320033
D/F#     200233 (Technically Dadd11/F# but who cares)
Em       022000
D        000232
C        032010

Try strumming the lower notes more predominantly to get the real bassy sound 
Justin has. Might not be 100% correct so feel free to add corretions/suggestions. 
The G might be a standard G but I never really play the higher strings when I play 
it anyway. Cheers.


[Verse]

       Em                       D       
Well I met you at the blood bank
        C
We were looking at the bags
          Em                  D
Wondering if any of the colors
                   C
Matched any of the names we knew on the tags

         G      
You said "see look it thats yours!
           D/F#
Stacked on top with your brother's
             Em
See how they resemble one another
              C
Even in their plastic little covers"

           C              Em       D       (Hold chords)
And I said I know it well


[Chorus]

     G
That secret that you knew
    D/F#
But don't know how to tell
   G
It fucks with your honor
    D/F#
And it teases your head
        Em
But you know that its good girl
        C
Cos its running you with red


[Verse]

          Em                    D       
Then the snow started falling
        C
We were stuck out in your car
         Em                       D
You were rubbing both of my hands
        C
Chewing on a candy bar

                     G
You said "'aint this just like the present
      D/F#
To be showing up like this"
          Em
There's a moon waning crescent
   C
We started to kiss

           C                Em             D
And I said I know it well


[Chorus]

G
That secret that we know
        D/F#
That we don't know how to tell
       G
I'm in love with your honor
       D/F#
I'm in love with your cheeks
            Em
What's that noise up the stairs babe?
        C
Is that Christmas morning creaks?

           C                Em             D
And I said I know it well
I know it well ...