The Complete Issue by Issue Reading Order - from Comic Book Herald

Avengers #12.1

    This Point One issue of Avengers acts as an off-hand Age of Ultron prologue, well before the actual events of AU. 

Avengers Assemble #14AU

Age of Ultron #1

Age of Ultron #2
Fantastic Four #5AU

    This Fantastic Four tie-in occurs chronologically before Age of Ultron #1. Personally I prefer to read it as it was published after the first two AU issues, with the universe of Ultron already established, but if you want to follow a more linear timeline, bump it before AU #1.

Superior Spider-Man #6AU

    Superior Spider-Man causes some unique continuity problems. For starters, you’ll definitely want to be caught up on the first few issues of Superior Spider-Man or find yourself smacked in the childhood with major spoilers. Second, Bendis’s Age of Ultron issues seem to ignore the major change within Superior, making for a mildly confusing debate on the state of Spidey in AU. Most importantly – the big reveal at the end of Age of Ultron #3 is actually teased for eagle-eyed readers in Superior. There’s an argument to be made to read Age of Ultron #3 first to save this surprise, but chronologically this book is before AU #3.

Age of Ultron #3

Age of Ultron #4

Ultron #1AU

    Chronology of this issue is very open. Largely standalone events, so you can really fit in at any point in the first six or so issues. Here works just fine, as published.

Age of Ultron #5

Wolverine & the X-Men #27AU

Age of Ultron #6

Age of Ultron #7

Avengers Assemble #15AU

Age of Ultron #8

Uncanny Avengers #8AU

Fearless Defenders #4AU

Age of Ultron #9

Age of Ultron #10

Age of Ultron: Epilogue #10AI

Avengers AI #1

Hunger #1 to #4