does rebalancing have costs 
yes it does it involves the fees related to the transactions to purchase and sell securities it can also involve the cost of performance for example to rebalance you might sell securities that have increased in value and pushed your allocations out of whack however you could miss out on a continued upswing in prices that those securities experience by making rebalancing part of an investment plan that you commit to you ll be aware of and can accept these and other potential costs in advance 