An anonymous source told SamMobile that the Galaxy Note 3 will be unveiled at the IFA technology trade show in Berlin in September, alongside the Galaxy Tab 3.
Samsung has not yet given any indication of future plans for the Galaxy Note or Galaxy Tab.
The firm announced the Galaxy Note 2 in August last year, although that was at a dedicated Unpacked launch event, not a trade show.
SamMobile's source also could not give any indication on specs for either the Galaxy Tab 3 or Galaxy Note 3.
Previous rumours have said that the Galaxy Note 3 will have an OLED screen measuring between 5.9 inches and 6.3 inches.
The device is likely to come with Samsung's new eight-core chip, or a quad-core processor in certain markets, such as the US and UK.
Samsung is also thought to be working on improvements to the S Pen stylus and touchscreen technology, following recent features introduced in the Galaxy S4 phone, such as eye-tracking and AirView touchless controls.
At Mobile World Congress, Samsung introduced the Galaxy Note 8.0 device, a quad-core tablet with a HD screen, 5-megapixel camera and running 4.1.2 (Jelly Bean).