Quick information about the capacity of any cross section for combined loading is very useful information at the early stages of engineering design. These combined loads can be pressure, axial force, bending moment and torsion, depending on application of cross section. Interaction formula based on limit loads is a very useful equation to estimate the capacity of any cross section for a combination of loads. For hollow circular cross section the complexity of interaction formulae depends on definition of limit state and type of loads. Interaction formulae for circular cross section with different limit state assumptions are easily available in literature for pressure, axial force and bending moment. This paper proposes interaction formulae for circular cross section with additional term of torsional moment at elastic limit load. © 2016 Elsevier Ltd.