This is a list of all the fanfics I can find in which Harry is either a phoenix animagus or he acquires some phoenix traits. If you know of one that I can add, please leave me a link in a comment!
() Not read
* Not the best
*** Very good
**** Highly recommended
The Ashes of Hope by Laer Ear ***
ABANDONED. Harry Potter was wrongly condemned to Azkaban, and a year later the 17-yr-old is Kissed and cremated. Only later does the Order discover his innocence, mere minutes too late. Is the light’s only hope now a pile of ashes or is it simply hidden? Phoenix animagus form.
Betrayal of the Best Kind by Draco664 ***
Complete. Harry is accused and sentenced for a crime he did not commit, but he survives and escapes Azkaban when he discovers his animagus form. Sequel: Midnight Duel, Midday Love (Complete). Alternate link (Yahoo Group). Phoenix anumagus form.
Betrayal of the Light by Hannibal ad Portas *
ABANDONED. AU postOotP. Harry gets a visit from Sirius, and realizes that if he wants to win the war, he must forge his own destiny. Of course, it's never that simple, is it? Betrayed, he must seek out new allies, and form an army of his own. Major HG. Phoenix animagus form.
Beyond My World by Light Avatar **
Complete. After his latest clash with Voldemort, Harry finds himself in a universe where Voldemort raised him to be a Death Eater. Can Harry get in touch with Dumbledore, convince him that he's not evil, and find a way home? AU after OotP, no ships. Very small plot point of Harry with Phoenix animagus form.
Dark Phoenix by Sofia Dragon **
WIP. Harry Potter ran away one day, tired of watching others suffer for his ignorance. He couldn't sit on the sidelines and wait for someone else to tell him what to do any more. Luck, as always, is on his side as he works to make a place for himself, not only in the war, but in life. Some very old magic is at work, allowing him to do far more then he thought he could. Phoenix animagus form--"storm phoenix" not fire phoenix.
Harry Potter and the Darkness Within by Dellacouer **
WIP. Alternate 6th year. Feeling lost in the truth of the Prophesy and THE death, Harry becomes convinced that his battle with Voldemort will end his life. But vows to take Voldemort with him. Travels to AU Fic. Phoenix animagus form.
Harry Potter and the End of a New Life by Mione5 *
Complete. Harry left the wizarding world halfway through his seventh year. Hiding in the muggle world for almost eighteen years he is suddenly dragged back as his children are sent their Hogwarts letters. Why did he leave? And does he really what to go back? Phoenix animagus form.
Harry Potter and the Freedom of Apathy by nonjon ()
Complete. PostOotP. After ten years in Azkaban Harry emerges a changed man. Enlightened and respectful, he is creature of magic full of disappointment and shame in his own race. And yet yielding power that none can match. Sequel: Harry Potter and the Apathy of Freedom (Complete). Phoenix animagus form.
Harry Potter and the Prophecy of the Phoenix by Story Spindler ***
Complete. Harry's fifth year will send him on a journey to discover his destiny and who he really is. Phoenix Animagus form.
Lightning on the Wave's Vates Series ****
Complete. This is a very long series! Somewhere in the fourth or fifth story in the series Harry acquires a few attributes of a phoenix.
Never Alone, Never Again by Bored Beyond Belief ****
Complete. Harry's holiday reaches it's lowest point. Will Harry finally be able to have the kind of love everyone else seems to take for granted? Connected vignette: Make a Joyful Noise Phoenix animagus form.
Past the scar by Mione5 *
Complete. Harry's shoulders are only so broad, so what happens when it all becomes too much. He just wants to be normal. He wants to find someone who can see past the scar. But who really can? Phoenix animagus form (but only very briefly mentioned at the end).
Stranger in an Unholy Land by Jono ****
Complete. Days before his 6th year, Harry Potter is sucked into another universe by forces not of this world. Dazed and confused, Harry finds himself in a world where his parents are alive, where Voldemort has never fallen and he is Voldemort's key enforcer. Alternate link (Yahoo group). Phoenix animagus form (occurs somehwere in the middle of the story).
Stockholm Syndrome by Hannibal ad Portas *
ABANDONED. AU: Sirius breaks out of Azkaban eight years early, and rescues Harry from the Dursleys. Eleven years later, Ginny is accidentally kidnapped....by Harry? HG. Phoenix animagus form.