Most organisations moving their legacy systems to the cloud base their decisions on the naïve assumption that public cloud always provides cost savings, without sufficiently assessing the underlying application architecture, and the technical and financial constraints that it imposes on the chosen cloud architecture. This can lead to undesirable consequences including project delays, budget overruns, below-par performance, application instability and creation of technical debt. In this paper, we address the shortcomings of this assumption by proposing a structured yet flexible decision framework comprising models, guidelines, tools and calculators that enables IT and/or business practitioners to make the correct architectural decision between public, private and hybrid cloud, from a functional, non-functional and financial perspective, based on the application architecture. By treating the application architecture as a first-class citizen in the decision making process, our proposed framework ensures that business and technical stakeholders make the correct decision early on in the migration process, resulting in timely deployment and quality-assured provision of critical business functions, minimization of waste, and avoidance of rework. We use a sample scenario to illustrate the need and usefulness of such a decision framework.