A: It depends. You can contribute from two or more sources if you earn income from these sources. This is referred to as the multiple contribution and must be done using the same SSNIT number you have. If it is not earned income from your employment, it cannot count as additional income. If it is your private business and you wish to contribute for it, you can contact SSNIT and after ascertaining that it is income earned, they can set you up to contribute. 

Alternatively, you can contribute to Tier 3 with an NPRA-approved trustee. Databank can assist you by referring you to a trustee when you get in touch.