Every insurance company or association not organized under the laws of this state, shall, as provided in section 148.350, quarterly pay tax upon the direct premiums received, whether in cash or in notes, in this state or on account of business done in this state, for insurance of life, property or interest in this state at the rate of two percent per annum in lieu of all other taxes, except as in sections 148.310 to 148.461 otherwise provided, which amount of taxes shall be assessed and collected as herein provided; provided, that fire and casualty insurance companies or associations shall be credited with cancelled or return premiums actually paid during the year in this state, and that life insurance companies shall be credited with dividends actually declared to policyholders in this state, but held by the company and applied to the reduction of premiums payable by the policyholder.