How to reach the owner
The only contact channel is e-mail: team@voittovirta.com. There is no contact form, no chat and no telephone number.
What to expect
Every message is read by a person and answered personally. There are no automated acknowledgements, so a silence of a few days means the message is in a queue, not lost. Messages in English, Finnish, Spanish, Italian, Portuguese, German, French or Dutch are all fine.
Data corrections
Reports of a wrong or missing figure are the most useful messages this site receives. Please include the date, the maturity, the value shown here and the value you believe is correct, together with the source you are comparing against, for example the Banco de España, the Banco de Portugal, the ECB Data Portal or your bank's statement. Figures are never edited by hand; a confirmed error is fixed by re-fetching the data from the source, and the methodology page is updated if the discrepancy turns out to be systematic.
Corrections to the explanatory text, especially about mortgage conventions in a specific country, are equally welcome.
What we cannot do
The site does not give personal financial advice. Questions of the form "should I fix my rate", "should I switch bank" or "what will Euribor do next year" will receive a polite reply explaining that this is not something an information site can or should answer. The site does not recommend banks, brokers or products, and it does not have access to your loan contract, so it cannot tell you which maturity or convention your own loan uses; your bank can.
Write to team@voittovirta.com. Messages are read by the owner; there is no automated reply.