2015

January

 * January 19: The Halo 5: Guardians Multiplayer Beta ends.
 * January 28: The fourteenth issue of Halo: Escalation is released.

February

 * The third series of Halo 4 McFarlane Toys is released.
 * February 25: The fifteenth issue of Halo: Escalation is released.

March

 * March 2: Halo: New Blood is released digitally.
 * March 17: Halo: Nightfall is launched digitally and on Blu-ray.
 * March 22: Season One of Hunt the Truth begins.
 * March 25:
 * The sixteenth issue of Halo: Escalation is released.
 * Halo Online is officially announced, with a closed alpha and beta test exclusively for Russia.
 * March 29: The Halo 5: Guardians trailers, All Hail and The Cost, are released.

April

 * April 6: Halo Online Closed Alpha started.
 * April 16: Halo: Spartan Strike is released for Windows devices and Steam.
 * April 20: Halo 5: Guardians Spartan Locke Armor Set Gamestop Ad is released.
 * April 21: Halo: Escalation Volume 2 is released.
 * April 22: The seventeenth issue of Halo: Escalation is released.

May

 * May 27: The eighteenth issue of Halo: Escalation is released.
 * May 30: Halo 3: ODST ' s campaign and the map Remnant are added to Halo: The Master Chief Collection.

June

 * June 1: The first Halo Online Closed Alpha update is released in Russia.
 * June 14: The final episode of Hunt the Truth Season 1 is released.
 * June 15: A demo of the Halo 5: Guardians campaign was shown, along with a cinematic trailer and a trailer for the new multiplayer mode, Warzone.
 * June 16: Halo: Hunters in the Dark is released.
 * June 17: The Sprint season two begins.
 * June 18: The second Halo Online Closed Alpha update is released in Russia.
 * June 24: The nineteenth issue of Halo: Escalation is released.

July

 * July 2: The third Halo Online Closed Alpha update is released in Russia.
 * July 20: The first box set for Halo: Fleet Battles, The Fall of Reach, is released.
 * July 21: The fourth Halo Online Closed Alpha update is released in Russia.
 * July 22: Two replicas of the D79-TC Pelican and the made by Dark Horse are released.
 * July 27: Halo: Saint's Testimony is released.
 * July 29: The twentieth issue of Halo: Escalation is released.

August

 * August 4: Halo Wars 2 is officially revealed at Gamescom 2015 for an Xbox One and Windows 10 PC release in Fall 2016.
 * The first series of Halo 5: Guardians McFarlane Toys is released.
 * August 14: The fifth and final update to the Halo Online Closed Alpha Test is released.
 * August 23: Recording for Hunt the Truth Season 2 started.
 * August 26: The twenty-first issue of Halo: Escalation is released.

September

 * September 11: Halo Online Closed Alpha ends.
 * September 15: Halo: Last Light is released.
 * September 22: Halo: Escalation Volume 3 is released, and Season Two of Hunt the Truth begins.
 * September 23: The twenty-second issue of Halo: Escalation is released
 * September 30: Halo Online Beta starts with the first Beta update.

October

 * October 5: The third season of The Sprint begins, releasing its first two episodes.
 * October 27:
 * Halo 5: Guardians, the second game in the Reclaimer Saga and the sequel to Halo 4, is released for the Xbox One.
 * The Art of Halo 5: Guardians is released.
 * Halo: The Fall of Reach - The Animated Series is available for those who pre-ordered the Halo 5: Guardians Limited or Limited Collector's editions.
 * Season Two of Hunt the Truth ends.
 * The third and fourth episode of The Sprint Season 3 are released.
 * October 28: A replica of the Truth and Reconciliation and the twenty-third issue of Halo: Escalation are released by Dark Horse.
 * October 30: Halo 5: Guardians Original Soundtrack is released.

November

 * November 17: The fifth and final episode of The Sprint Season 3 is released.
 * November 18: The Battle of Shadow and Light content update for Halo 5: Guardians is released.
 * November 25: The twenty-fourth and last issue of Halo: Escalation is released.

December

 * December 1: Halo: The Fall of Reach - The Animated Series is released on Blu-ray and DVD.
 * December 2: The second Halo Online Beta update is released in Russia.
 * December 4: Halo: The Fall of Reach Original Soundtrack is released.
 * December 7: Halo: Shadow of Intent is released.
 * December 16: The Cartographer's Gift content update is released for Halo 5: Guardians. The update includes the addition of Forge mode and four multiplayer maps.
 * December 28: Halo Online closed Beta test is suspended because of serious problems during the game's development.