Some of the tanning lotions do not have the expiry date. So a question may arise that how long is tanning lotion good for. In such a case we cannot continue using that one because that tanning lotions or oil is formed of some chemical compounds which are those have got some limited time duration to be used.
After the expiry date, it would be very damaging to be used for skin & the products also may lose their effectiveness suddenly. So actually the usable time depends on the manufacturer. Normally these last for 1.5-3 years. In the USA it’s a detainable thing not to have the expiry date on the body. If these are not preserved at air-conditioned room or lower temperature also then these things may get their functions weakened & these might get their functional life shortened also.
Some cases these may produce a very bad scent also as these are having DHA (dihydroxyacetone). By testing the scent also we might understand the situation or condition of the tanning lotion/oil. We cannot expect the maximum output also from the expired tanning lotion. We can ask the company also about the expiry date of that tanning lotion.