Lyrics:

[Verse 1: Niall]
When I'm fat and old
And my kids think I'm a joke
Because I move a little slow when I dance

[Hook: Liam]
I can count on you
After all we got up to
'Cause I know that you'll always understand

[Chorus: All]
I won't act my age
No, I won't act my age
No I'll still feel the same around you

[Verse 3: Louis]
When I'm fat and old
And my kids think I'm a joke
Because the stories that I've told
I tell again and again

[Hook: Zayn]
I can count on you
After all we got up to
Because I know that you'll truly understand

[Chorus: All]
I won't act my age
No, I won't act my age
No, I'll still feel the same around you
I won't act my age
No, I won't act my age
No, I'll still feel the same and you will too

[Bridge: Harry]
When I can hardly walk and my hair is falling out
We'll still stay up 'til morning
We'll throw an after party
Oh yeah, oh yeah!

[Chorus: All]
I won't act my age
No, I won't act my age
No, I'll still feel the same around you
I won't act my age
No, I won't act my age
No, I'll still feel the same and you will too