Small Business Election Simplification Act - Amends the Internal Revenue Code, with respect to the subchapter S election for corporate taxpayers, to: (1) extend the deadline for filing such election to the due date (with extensions) of the corporation's tax return, (2) authorize the Secretary of the Treasury to treat a late filing or revocation of an election as timely filed or revoked if there is reasonable cause for failing to make a timely filing or revocation, and (3) allow taxpayers to make a subchapter S election on their current tax return in lieu of filing a separate form for making such election.