Abstract A flexible Discontinuous Reception (DRX) scheme is proposed to resolve the drawbacks of State-of-the-Art (SOTA) DRX scheme by eliminating the need of major timers and allowing Intra-Subframe Micro (ISM) sleep periods. The proposed new Timer Eliminating DRX (TE-DRX) scheme was tested and analyzed with traffic logs from live mobile network. This scheme can drastically reduce the active time of mobile devices by more than 75% and can thereby save at least 40% of energy to be used and improve battery life compared to practical technology limit of (SOTA) solution. It is shown that scheduling can be made relaxed. That is, the system is not forced to schedule data for (DRX) users in the first subframes of radio frames, and good performance does not require scheduling user data in consecutive subframes (like in case of short On-duration timers). Thereby it is possible to save energy even in heavily loaded systems and make very efficient (DRX) reality in legacy networks comparable to 5th Generation (5G) sleep mode proposals. Moreover, the proposed method can be considered as a possible extension of upcoming (5G) networks, as well.