This batch file was updated on August 22, 2018.

Reading order:
Volume 1-13
Volume SS1
Volume 14-16
Volume SS2
Volume 17-22
New Testament series

Season 1 of the Index anime covered volumes 1-6. Season 2 covered volumes 7-13+SS1. If you have seen season 1 and 2 and want to know where to pick up the novels from,
I would urge you start at the very beginning. However, if you really don't want to do that, my suggestion would be to read chapter 3 of volume SS1, which wasn't adapted in season 2,
then start at 14. Additionally, you may want to read the epilogue of volume 6 and the epilogue of volume 13 for further clarification of future events.


For side stories:
Volume SP and Kanzaki SS should be read at some point before starting New Testament. I would recommend reading them after either volume 18 or 22.


For the remaining side stories, I will list what volume the story was on when the side/parody story was released.
Be aware that several of these stories will contain characters and spoilers for events up to the listed volume.

I don't necessarily recommend reading these right after you've read the listed volumes. This is here to give you context to when they were released and to avoid spoilers.


Side stories:
Railgun SS - Last part was released after volume 18.
Toaru Jihanki no Fanfare - Released after volume 19.
Love Letter SS - Released after volume 22.
Railgun SS2 - Last part was released after NT2.
Railgun SS: A Superfluous Story - Released after NT3. It is meant to be an epilogue story to the Railgun PSP game.
Road to Endymion - Released after NT6.
Necessarius SS - Last part was released after NT9.
New Testament SS - Released after NT10.
Toaru Majutsu no Virtual-On - Released after NT15.
A Certain Midsummer Return to the Starting Point - Released after NT16.
Using Final Bosses to Determine a Sociological Threat - Bundled with NT17.
NT18 Bonus Story - Bundled with NT18.
Thus Spoke the Kumokawa Sisters - Bundled with NT19.
Railgun Cold Game - Released after NT19.
Virtual-On: Vooster's Cup, The Day Before - Released after NT19. Bundled with the limited edition of the Virtual-On game.
Virtual-On: Misaka Mikoto's Dangerous Tea Party - Released after NT19.
Birthday Through the Glass - Released after NT19.
NT20 Bonus Story - Bundled with NT20.


Parody stories:
A Certain Prophecy Index - Released after volume 5.
A Certain Academy Index - Released after volume 6.
A Certain March Gift Exchange - Released after volume 11.
A Certain March 201st Volume - Released after volume 11.
I Don't Want this First Story - Released after volume 14.
A Certain Collaboration - Released after NT7.
Kamijou-san, Two Idiots,... - Released after NT16.
We Tried Having a Group Blind Date... - Released after NT17.
Will the Spiky-Haired Idiot... - Released after NT18.