Well, according to RBI's current rules, locker compensation is capped at 100 times the annual rent for losses due to bank negligence (theft, fire, or fraud). So, for your ₹8,000 Kotak locker, you’re covered for up to ₹8 lakh.
SBI’s metro medium locker fees are lower at ₹4,000 + GST. Switching to SBI can save you about ₹40,000–50,000 over ten years. If you want better service and quick access, Kotak’s higher fees make sense. However, if you're looking for safety at a reasonable price, moving to a PSU bank is a smart choice for the long run.