During the past two decades, the comprehensive multi-year planning (cMYP) process has been the cornerstone of strategic planning for immunization as part of the Global Vaccine Action Plan (2011-2020). However, a series of reviews highlighted persistent challenges. During 2016-2017, a rapid assessment of immunization planning recommended improving strategic and annual operational planning for immunization, including making the cMYPs more strategic, ensuring direct linkages between cMYP and annual operational plans, and simplifying the cMYP costing tool. Following a review of existing costing tools and a consultative process involving a Steering Committee, a new approach has been developed; the National Immunization Strategy costing application (NIS.COST). This new approach has been designed for easy use and better integration with the national immunization strategic plan and the overall budgeting processes. The NIS.COST application has a setup tab that requires the user to complete country specific information and five main sections. There is a support tab to seek help from the developers.