Series I Have Read (As of February 2015)

Series I Have Completed (not counting novellas or books that are set in the same world but in a different series):

1. The Darkest Powers by Kelly Armstrong (3 books)
2. The Grisha by Leigh Bardugo (3 books)
3. Graceling by Kristin Cashore (3 books)
4. The Mortal Instruments by Cassandra Clare (6 books)
5. The Infernal Devices by Cassandra Clare (3 books)
6. The Hunger Games by Suzanne Collins (3 books)
7. The Maze Runner by James Dashner (4 books)
8. The City of Ember by Jeanne Duprau (4 books)
9. Legend by Marie Lu (3 books)
10. Shatter Me by Tahereh Mafi (3 books)
11. Vampire Academy by Richelle Mead (6 books)
12. Keys to the Kingdom by Garth Nix (7 books)
13. The Inheritance Cycle by Christopher Paolini (4 books)
14. The Kane Chronicles by Rick Riordan (3 books)
15. Percy Jackson and the Olympians by Rick Riordan (5 books)
16. The Heroes of Olympus by Rick Riordan (5 books)
17. Divergent by Veronica Roth (3 books)
18. Harry Potter by J. K. Rowling (7 books)
19. Septimus Heap by Angie Sage (7 books)
20. Daughter of Smoke and Bone by Laini Taylor (3 books)
21. Uglies by Scott Westerfeld (4 books)
22. The Secret Series by Pseudonymous Bosch (5 books) 
23. Eon by Alison Goodman (2 books)

Series in which I have read all the books that have come out so far (not counting novellas or books that are set in the same world but in a different series):

1. Magisterium by Cassandra Clare and Holly Black (1 book out so far)
2. Princess Academy by Shannon Hale (2 books out so far)
3. Seraphina by Rachel Hartman (1 book out so far)
4. The Lorien Legacies by Pittacus Lore (5 books out so far)
5. The Young Elites by Marie Lu (1 book out so far)
6. Throne of Glass by Sarah J. Maas (3 books out so far)
7. Bloodlines by Richelle Mead (5 books out so far)
8. The Lunar Chronicles by Marissa Meyer (3 books out so far)
9. The Old Kingdom by Garth Nix (4 books out so far)
10. Snow like Ashes by Sara Raasch (1 book out so far)
11. Falling Kingdoms by Morgan Rhodes (3 books out so far)
12. The Raven Cycle by Maggie Stiefvater (3 books out so far)
13. The Elemental Trilogy by Sherry Thomas (2 books out so far)
14. The 5th Wave by Rick Yancy (2 books so far)
15. To all the Boys I've Loved Before by Jenny Han (1 book so far) 
16. The Winner's Curse by Marie Rutkoski

Series I Have Started but Have not Finished (In all of these I have finished at least the first book):

1. The Hitchhiker's Guide to the Galaxy by Douglas Adams (5 books, I've read the first 3)
2. Ender's Game by Orson Scott Card (I've read 4 books and there are, like, 20 billion
3. The Selection by Kiera Cass (3 books out so far, I've read 2)
4. Young Wizards by Dianne Duanne (I've read 1 book and I have no clue how many there are)
5. Fablehaven by Brandon Mull (5 books, I've read the first 2)
6. The False Prince by Jennifer Nielsen (3 books, I've read 2)
7. Miss Peregrine's Home for Peculiar Children by Ransom Riggs (2 books out so far, I've read 1)
8. Under the Never Sky by Veronica Rossi (3 books, I've read 1)
9. The Lord of the Rings (I've read LOTR and the Hobbit, but not anything else in this series)
10. Dustlands by Moira Young (3 books, I've read 2)
11.  A Wrinkle in Time by Madeleine L'Engle (I've read 1 book and there are 5 total)
12. The Giver by Lois Lowry (I've read 1 and there are 4 total)
13. Ash by Malinda Lo (I've read 1 of 2 books)
14. Sherlock Holmes by Arthur Conan Doyle (I've read 1 of a million)
15. Hercule Poirot by Agatha Christie (I've read 5 of a million)

BONUS: Books I have Read that are not in Series:

1. I am the Messenger by Markus Zusak
2. The Book Thief by Markus Zusak
3. The Invention of Hugo Cabret by Brian Selznick
4. Wonderstruck by Brian Selznick
5. Ella Enchanted by Gail Carson Levine
6. Book of a Thousand Days by Shannon Hale
7. An Abundance of Katherines by John Green
8. The Fault in our Stars by John Green
9. Paper Towns by John Green
10. Looking for Alaska by John Green
11. Walk Two Moons by Sharon Creech
12. And the There were None by Agatha Christie
13. The Perks of Being a Wallflower by Stephen Chbosky
14. We Were Liars by E. Lockhart\
15. The Scorpio Races by Maggie Stiefvater