Businesses, governmental bodies and NGO's have an ever-increasing amount of data at their disposal from which they try to extract valuable information. Often, this needs to be done not only accurately but also within a short time frame. Clean and consistent data is therefore crucial. Data matching is the field that tries to identify instances in data that refer to the same real-world entity. In this study, machine learning techniques are combined with string similarity functions to the field of data matching. A dataset of invoices from a variety of businesses and organizations was preprocessed with a grouping scheme to reduce pair dimensionality and a set of similarity functions was used to quantify similarity between invoice pairs. The resulting invoice pair dataset was then used to train and validate a neural network and a boosted decision tree. The performance was compared with a solution from FISCAL Technologies as a benchmark against currently available deduplication solutions. Both the neural network and boosted decision tree showed equal to better performance.