A sublimit is a deviating upper limit within the insurance contract for an insurance policy. Sum insured.

For example, in personal liability insurance, the Sum insured for property damage up to 10 million euros, but the co-insured rental property damage is only insured up to a sub-limit of 100,000 euros.

 

Source reference: See VDT publication "VDT article series part 5 l Glossary" and the source indicated there.