I don't know if there is other little riffs he plays, but I'm almost certain that
this is used pretty much through the whole song. Otherwise let me know :)
Capo: 7th Fret
[ Tab from: https://www.guitartabs.cc/tabs/p/passenger/circles_tab.html ]
Am G Am G Am
e|----------------------------------------------------------------------------|
B|----1------------0h1p0----------1------------0--3p1p0h1-----1---------------|
G|--------2---2----------0---0--------2---2-----------------------2---2-------|
D|----2-----2------0-------0------2-----2------0--0-----------2-----2---------|
A|--0---0-----------------------0---0-----------------------0---0-------------|
E|---------------3----------------------------3-------------------------------|
G Em D
e|-----------------------------------0h1p0-------------REPEATE----------------|
B|----0h1p0-----------0--------------------3---3------------------------------|
G|----------0---0---------0---0------2-------2---------REPEATE----------------|
D|----0-------0-------2-----2------0------------------------------------------|
A|-----------------------------------------------------REPEATE----------------|
E|--3---------------0---0-----------------------------------------------------|
p: pulloff
h:hammer on