While the bulk of financial efficiency and competition research tends to conclude that there is a relatively sound price formation process in most of our domestic financial markets, this view is certainly not unchallenged in the business press and the media in general. It is often argued that the oligopoly structures of the dominant market players (often in the form of the big banks) lead to competitive restrictions in the market. According to SKI, despite a lower level of customer satisfaction with the major banks compared to other banks, only about 3% of consumers switch banks per year. Although the dominance of the major banks has declined somewhat, the passive customer mobility of consumers means that the incentives of the major market players for strong price competition are relatively low. The project therefore unconditionally investigates whether there is a greater propensity for banks to raise customers' mortgage rates (both in terms of level and time) after borrowing cost increases, compared to the propensity to lower mortgage rates after corresponding borrowing cost reductions. Through a unique dataset, we measure banks' marginal borrowing costs, whereas the risk premium is difficult to measure. Changes in the risk premium can justify keeping mortgages unchanged despite repo or interbank rate cuts, but our new asymmetry method takes into account the level of the risk premium. For a large set of interest rates, times, frequencies and methods, we analyze whether banks charge a justified risk margin in addition to the marginal cost.