The purpose of the article is to answer the question whether, with regard to the limitation period for claims arising from a contract of carriage under the Convention on the Contract for the International Carriage of Goods by Road (CMR), the principle provided for in Article 118, second sentence, of the Civil Code, according to which the end of the limitation period of at least two years falls on the last day of the calendar year, should be applied. The author bases these reflections on the premise that since the CMR Convention does not regulate international road transportation comprehensively, it is necessary to apply the relevant domestic law in the unregulated area. If this were Polish law, then the application of Article 118, second sentence, of the Civil Code may be considered with regard to the issue of the statute of limitations. The article presents both arguments for and against such a view. Ultimately, the author comes to the conclusion that the mechanism for extending the limitation period to the end of the calendar year should not be applied to the limitation periods provided for in the CMR Convention.