Power headroom management in uplink carrier aggregation for connectivity with logically separate cells of a wireless communications system is performed by a network entity, alone or in combination with another network entity, one or more mobile entities, or both. This may include determining an uplink power allocation across at least two independently controlled cells of a wireless communication network for a mobile entity served by at least two independently controlled cells of a wireless communication network, subject to a total PH constraint for uplink transmissions by the mobile entity. A network entity may then manage PH reporting for determining the uplink power allocation by the uplink serving cells, based on the determined uplink power allocation. Managing the PH reporting may be performed by at least one of: explicit coordination between the at least two independently controlled cells, implicit coordination between the at least two independently controlled cells, or configuring PH reporting from the mobile entity by at least one of the at least two independently controlled cells.