Yes, eHerkenning EH3 is suitable for filing your dividend tax return. You can apply for a regular eHerkenning EH3but also the Limited Belastingdienst EH3 login tool is also suitable for this purpose.
If you already have eHerkenning but no Dividend Tax Authorization, you can add an additional authorization EH3 add to your eHerkenning by logging on to My Reconi.
If you already have the Restricted Belastingdienst EH3 login tool, you do not need to add anything to your eHerkenning. You will have automatic access and can log in at Belastingdienst for your Dividend.