48. Do political parties have to report on their election campaign finances?

Section 8.2 Declaration of Income and Expenses of Elections 
(1) Political organisations (parties) which have submitted lists of candidates thereof for the elections of the Saeima, local government council, or the European Parliament shall, within 30 days after the elections of the Saeima, local government council, or the European Parliament, submit a declaration of income and expenses of elections signed by the representative of the relevant political organisation (party) to the Corruption Prevention and Combating Bureau using the Electronic Data Input System in accordance with the procedures stipulated by the Cabinet. (2) The declaration of income and expenses of elections shall disclose all the revenues and expenses which have been incurred over the period from the 120th day before the elections up to the election day, regardless of the date when a document attesting the transaction has been written out (invoice, contract or other document), the payment for the following is received or performed: 1) placement of an advertisement: a) on public television; b) on public radio; c) on commercial television; d) on commercial radio; e) in newspapers, magazines, bulletins and other periodicals registered in accordance with the procedures laid down in the law, produced by print technology and widely circulated throughout the whole territory of the State; f) in newspapers, magazines, bulletins and other periodicals registered in accordance with the procedures laid down in law, produced by print technology and for which the largest part of circulation is being distributed in the territory of a single republic city or district; g) on the Internet, except for the website of the political organisation (party); h) in premises and public places (in squares, streets, on bridges and in other similar places) regardless of the ownership.
Law on Financing of Political Organisations (Parties) Article 8.2.

30 days after election.