We present analyses of new optical photometric observations of three W UMa-type contact binaries FZ
Ori, V407 Peg and LP UMa. Results from the first polarimetric observations of the FZ
Ori and V407 Peg are also presented. The periods of FZ
Ori, V407 Peg and LP UMa are derived to be 0.399986, 0.636884 and 0.309898 d, respectively. The
O?
C analyses indicate that the orbital periods of FZ
Ori and LP UMa have increased with the rate of 2.28×10
?8 and 1.25×10
?6 d?yr
?1, respectively and which is explained by transfer of mass between the components. In addition to the secularly increasing rate of orbital period, it was found that the period of FZ
Ori has varied in sinusoidal way with oscillation period of ~30.1 yr. The period of oscillations are most likely to be explained by the light-time effect due to the presence of a tertiary companion. Small asymmetries have been seen around the primary and secondary maxima of light curves of all three systems, which is probably due to the presence of cool/hot spots on the components. The light curves of all three systems are analysed by using Wilson-Devinney code (WD) and the fundamental parameters of these systems have been derived. The present analyses show that FZ
Ori is a W-subtype, and V407 Peg and LP UMa are A-subtype of the W UMa-type contact binary systems. The polarimetric observations in
B,
V,
R and
I bands, yield average values of polarization to be 0.26±0.03, 0.22±0.02, 0.22±0.03 and 0.22±0.05 per cent for FZ
Ori and 0.21±0.02, 0.29±0.03, 0.31±0.01 and 0.31±0.04 per cent for V407 Peg, respectively.
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