OBJECTIVES: While pharmacoeconomic research is often used as a tool to assist decision on product reimbursement, Budget Impact Analysis (BIA) is increasingly required by decision-makers to ascertain the macroeconomic consequences of new product reimbursement in addition to proof of cost-effectiveness. BIA provides insight into financial consequences of reimbursing a new technology. Poland is in the process of drafting country-specific guidelines for BIA, positioned as complementary to economic evaluation in decision making. The aim of this study is to compare project of Polish BIA guidelines with existing international guidance, highlighting areas of agreement and dissent. METHODS: Guidelines from 5 countries (Australia, Canada, Netherlands, England & Wales, France, USA) were reviewed, analyzed and comparison was undertaken. The following areas were analysed: objective, use of BIA, responsibility in their conduct, target audience, methodology and ethical code of practice while conducting and in the publication of results. An analysis of the differences between different national guidelines and their Polish counterparts was subsequently undertaken. RESULTS: Current international guidance for BIA is limited, often unclear and variable in terms of defining what constitutes BIA and how it should be undertaken. Australian PBAC guidelines for economic evaluation provide most detail into how BIA should be undertaken and reported. In comparison to existing guidance project of Polish BIA guidelines appears to be more detailed and includes recommendations on perspective, time horizon, reliability of data sources, reporting of results, rates of adoption of new therapies, probability of re-deploying resources. The intention was to establish principles for best practice in designing and implementing BIA. CONCLUSIONS: Whilst there is an increased demand for BIA, there is only limited guidance on how such studies should be undertaken. It is hoped, that the Polish guidelines can contribute to the development of such analyses and deliver benefit for Polish healthcare decision makers and beyond.