We have designed and fabricated a low‐noise dc superconducting quantum interference device (SQUID) magnetometer that is integrated on a 4×4 mm2chip. The white flux noise of the magnetometer measured in a flux‐locked‐loop mode using simple, direct‐coupled electronics with additional positive feedback (APF) is 6.4×10−7&Fgr;0/&sqrt;Hz. The corresponding white flux density noise is 3.9 fT/&sqrt;Hz. The SQUID flux‐to‐voltage transfer function with APF is enhanced to 4.7 mV/&Fgr;0at the optimal working point, thereby significantly reducing the preamplifier contribution to the total noise. A maximum feedback field of 65 nT for frequencies up to 300 Hz and a maximum slew rate of 120 &mgr;T/s at 300 Hz have been attained using a two‐pole integrator.