Interest deduction limitation rules have an important function as the regulations prevent the Swedish tax base to decrease. However, the restrictions must not be at the expense of the business environment. Interest deduction limitation rules that do not work in a satisfactory manner are likely to make Sweden a less favourable country to establish in.

The first Swedish rules which were aimed to restrict interest deduction threaded into force in 2009. The rules were applicable to intercompany loans related to acquisitions of part ownership rights and the aim was to reduce tax avoidance through corporate group-loans. The rules proved to be ineffective since the avoidance continued and the Swedish rules could not tackle the problem. The rules were revised and in 2013 Sweden implemented new restrictions regarding interest deduction rules that were applicable to corporate group-loans, regardless of what the loan would be used for. The new rules were strongly criticized by several consultive bodies for being unpredictable for the liable of    taxation. The rules have also been criticized by the European Court of Justice for breaches EU law. A future modification of the existing interest deduction limitation rules is therefore highly likely.

The present thesis presents two alternative approaches to the Swedish interest deduction limitation rules, thin capitalization rules and the tax credit method, which is a new proposal by Sven-Olof Lodin. Sweden should wait to introduce thin capitalization rules since the rules in several member states have been criticized for not being compatible with EU law. Furthermore, it is stated in the thesis that thin capitalization rules will not remove the incentive for tax planning. This is because companies can easily customize loan to not exceed the ratio of the relationship between equity and internal debt, which governs whether a company is thin capitalized or not. The advantage of the thin capitalization rules is that they could possibly increase the predictability of the rules and that the rules can be quite legally secure. Another advantage is that thin capitalization rules could contribute to an international harmonization of tax rules regarding corporate group-loans, since it is a common practice in other member states. Although, the benefits do not weigh up for the disadvantages and Sweden is therefore recommended to wait to implement the thin capitalization rules.

The proposal from Lodin to introduce a tax credit system is something that Sweden is recommended examining. The advantage of the system is that it is the most effective, out of the three methods, since the system removes the incentive to tax planning. Since the rules is not a deduction method but instead a reduction method, the lending company's corporation tax is not an essential factor in raising loans. This creates tax neutrality for the corporate group. Since the rules have not been introduced in any member states, it is difficult to compare the rules with other rules as well as to get a full picture of what disadvantages such rules could result in.

The thesis shows that the problem is not to develop rules that effectively prevent tax avoidance with corporate group-loans. More problematic is it for countries to develop rules that are compatible with EU law and protects an attractive business environment. Sweden is in need of a system that has a better balance between protecting the interest of an attractive business environment and at the same time protects the Swedish tax base. The thesis presents a set of advantages and disadvantages focused on different methods and it does not exist an obvious method to replace the current Swedish rules. Although, the final recommendation of the thesis is to examine Lodins methods of preventing tax avoidance more closely.