When possessed by or bonded with the Phoenix Force, Jean's powers escalate to an incalculable level, allowing her to rearrange matter at a subatomic level, fly unaided through space, survive in any atmosphere, manipulate electromagnetic and cosmic energies for various effects and atmospheric disturbances. At this level, she is powerful enough to easily defeat a herald of Galactus.[60] She can also create stargates that can transport her to anywhere in the universe instantaneously.
As the Phoenix, Jean can resurrect herself after death and is unaffected by the passage of time. Though initially perceived as "borrowing" the powers of the Phoenix Force, due to her original status as a host for the Force, they are entirely her own; Death itself has said that Jean is the rightful owner of those powers.[14] She later becomes one with the Phoenix Force (as opposed to serving as its host) due to her status as an Omega-level mutant with unlimited potential, in which it was revealed that Jean holds the unique role of "White Phoenix of the Crown" among the many past, present, and future hosts of the Phoenix.[51] As the White Phoenix, Jean can manipulate and control whole timelines, as seen when she brought the alternate future of Here Comes Tomorrow into the White-Hot Room.[51] The Phoenix Force allows Jean to revive, absorb, rechannel, and preserve the life-force of any kind of life-form, meaning that she can take life energy from one person and give it to others, heal herself with the same life energy, or even resurrect the dead, since the Phoenix is the sum of all life and death.[14]