The realization of harmful effects of Pb on the atmospheric pollution, environment and human health requires full implementation of new generation of lead-free solders, requires detailed knowledge and understanding of their mechanical behavior. This study reports on structure, thermal and tensile creep properties of Sn–5 wt.%Sb–0.5 wt.%Ag (SSA505), Sn–5 wt.%Sb–1.0 wt.%Ag (SSA510) and Sn–5 wt. %Sb–3.0 wt.%Ag (SSA530) lead-free solder alloys. The obtained results show a surprising desirable decrease in melting temperature with increasing Ag content. Microstructure of the three solder alloys is characterized by the presence of square flat intermetallic compound (IMC) of SbSn particles within β-Sn matrix besides Ag3Sn IMC. Increasing Ag content led to the increase in size of the Ag3Sn particles along with an increase in its volume fraction. A remarkable decrease in the size of β-Sn grains is occurred with increasing Ag content. This reduction in size can be attributed to pinning effect of β-Sn grains by Ag3Sn fine IMC particles. Attention has been paid to the role of IMCs on creep characteristics. In order to relevant the creep characteristics such as stress exponent and activation energy, the tensile creep tests were performed within the temperature range 293–373 K at constant applied stresses. Activation energy (Q) and stress exponent (n) were determined to clarify the deformation mechanism. This study revealed that the solder alloy Sn–5Sb–3.0Ag has potential to give a good and higher creep resistance and lower melting.