Device for reusing greywater, comprising: - a water feed for supplying greywater; - a collecting reservoir for collecting the supplied greywater; - a storage tank for storing water; - transferring means for transferring water from the collecting reservoir to the storage tank; - a water discharge for discharging stored water to a water user; - a sewer outlet; and - a control system (20,24,43); - the collecting reservoir comprising an overflow and a bypass conduit, wherein the overflow is arranged on a top side of the collecting reservoir, wherein greywater flows away via the overflow into the bypass conduit, and wherein the bypass conduit is configured to divert greywater to the sewer outlet; - wherein the transferring means comprises a transfer connection between the collecting reservoir and the storage tank, said transfer connection being configured to transfer water from the collecting reservoir to the storage tank; - the transferring means further comprising a filling valve; - the device further comprising a sensor configured to detect when water overflows via the overflow into the bypass conduit or receiving means for receiving supplied greywater, when the collecting reservoir overflows through the bypass conduit, wherein the sensor is or the receiving means are connected to the filling valve; - wherein the transferring means are controllable by the control system, - wherein the filling valve is configured to open and thereby allow air to escape from the storage tank when water overflows through the bypass conduit, detected by the sensor or received by the receiving means; and - wherein the transfer connection is arranged substantially in a central part of the substantially vertically arranged collecting reservoir and is configured to transfer water that is situated substantially in this central part. - a water feed for supplying greywater; - a collecting reservoir for collecting the supplied greywater; - a storage tank for storing water; - transferring means for transferring water from the collecting reservoir to the storage tank; - a water discharge for discharging stored water to a water user; - a sewer outlet; and - a control system (20,24,43); - the collecting reservoir comprising an overflow and a bypass conduit, wherein the overflow is arranged on a top side of the collecting reservoir, wherein greywater flows away via the overflow into the bypass conduit, and wherein the bypass conduit is configured to divert greywater to the sewer outlet; - wherein the transferring means comprises a transfer connection between the collecting reservoir and the storage tank, said transfer connection being configured to transfer water from the collecting reservoir to the storage tank; - the transferring means further comprising a filling valve; - the device further comprising a sensor configured to detect when water overflows via the overflow into the bypass conduit or receiving means for receiving supplied greywater, when the collecting reservoir overflows through the bypass conduit, wherein the sensor is or the receiving means are connected to the filling valve; - wherein the transferring means are controllable by the control system, - wherein the filling valve is configured to open and thereby allow air to escape from the storage tank when water overflows through the bypass conduit, detected by the sensor or received by the receiving means; and - wherein the transfer connection is arranged substantially in a central part of the substantially vertically arranged collecting reservoir and is configured to transfer water that is situated substantially in this central part.