Yes, combined single limit (CSL) coverage gives you more liability coverage than a split limit policy, in its own way. And it costs more, too.
Split-limit liability coverage allocates three limits specifically for bodily injury (BI) per person, bodily injury per accident, and physical damage (PD) per accident. CSL has one overall limit that can be divided up for bodily injury or property damage by the needs of the claim.
Say you are at-fault in an accident and have split liability limits of 25/50/25, which stands for $25,000 per person injured and $50,000 for all injuries, plus $25,000 for the property damage liability portion.
In the accident, there are two individuals with $30,000 worth of injuries and the property damage amount is $26,000. Your split-limit policy would pay the injured parties each up to your $25,000 per person BI limit, leaving you personally responsible for the extra $5,000 per person ($10,000 total) that your insurance did not pay. You are also responsible for $1,000 that your PD liability limit did not cover.
Now, if you had combined single-limit coverage of $100,000 in the same accident, the funds could be allocated per your needs. Your policy could pay each injured party $30,000, for a total of $60,000 going toward BI claims. Your policy could also pay out the whole $26,000 for damage to the other vehicle. Here, all your claims are paid out, and you haven't reached your CSL limit.
If you are asking if combined single limit coverages cost more than split limits, then the answer is also yes. Because CSL puts the car insurance company at the risk of having a higher immediate payout, it usually is more expensive to carry than split-limits coverage.
Look at the split-limit policy mentioned above of 25/50/25. If one party is injured the most the insurer could pay out is $25,000. With a CSL policy of $100,000, the insurance company could be responsible for $100,000 from just one injury.
The availability of these different forms of coverage varies from insurance company to insurance company, as do the rates for each. Whether you are looking an auto insurance quote with combined single limit or split limit, CarInsurance.com can help you find the best rates available.