Yes. When you come to sell your property the chances are that a buyer will have a mortgage. The tendency over the last few months has been for lenders to tighten their requirements for the minimum number of years remaining under the lease (please see http://www.cml.org.uk/handbook/frontpage.aspx) and the fact that you have a share of the freehold does not mean that the buyer’s conveyancing lawyer will not be concerned about the remaining number of years under the lease.
The real value in what you are selling is the leasehold title rather than the freehold title. As it is the leasehold security that the bank are charging they will be concerned about the number of years remaining. In the circumstances, it is sensible for a tenant with a lease which has less than 80 years remaining to extend the lease if they have a share of freehold.
In most cases no money will be paid but you may be responsible both for the freehold company’s conveyancing solicitor’s lease extension fees as well as your own conveyancing solicitor’s lease extension fees and possibly even the lender’s conveyancing solicitor’s fees (please see above). Please note the comments above concerning the fact that it may well take a few weeks to conclude the lease extension even in the case where there is a share of freehold. It is generally cost-effective for all the tenants in the building to complete their lease extension at the same time so as to save lease extension fees.