Heated Tobacco Products (HTP) were developed as better alternatives to cigarettes to avoid the release of thousands of chemicals formed when the tobacco is being burnt. One such HTP is the Electrically Heated Tobacco System (EHTS) (from Philip Morris International), in which the tobacco material in the Electrically Heated Tobacco Product (EHTP) is heated instead of being burnt. The significant reduction in emissions from EHTPs compared to combusted cigarettes have been extensively substantiated by independent research groups. The absence of solid particle emissions from the EHTP has also been confirmed in published research. As EHTPs have filter elements between the tobacco portion and the mouth-end, their role associated to the conclusion that no solid particles are formed during use has never been investigated to our knowledge. In this work, aerosol collected from the EHTP with and without filter elements during heating as well as without heating was studied to investigate whether solid particles were formed in any part of the product during use. Two different analytical methods were used and the results from both methods showed that no solid particles originating from thermal processes was present in the EHTP aerosol.