Sustainability pressure on the packaging industry has increased considerably in recent years, with stricter regulation on recyclability and waste management along with heightened consumer awareness on the environmental impact of packaging. One critical measure that must be taken is to increase the recycling rates of all fiber-based packaging placed on the market, where in the EU this requirement has been set to at least 85% by the year 2030. Similar trends are being observed world-wide. This is creating an increased demand for using recycled fibre in packaging materials and with it an increased need for methods to ensure the quality of recycled fibre and final product performance. This trend also creates a risk for the availability of high-quality recycled fibre but also potential contamination of recycled fibre streams with other, low-quality materials, and producers may be forced to work with lower quality recycled materials in the future. This study investigates possible routes for upgrading recycled fibre quality through combined fractionation and refining strategies. A recycled pulp for containerboard was fractionated in pilot scale using a pressure screen and hydrocyclones. The pulp was first fractionated using a micro-perforated screen basket into a long fibre fraction and short fibre fraction, after which hydrocyclone fractionation was made on each screened fraction. Hydrocyclone fractionation of the screen short fraction resulted in a fine fraction with fibrillar fines and a coarse fraction containing low bonding fines, fibre fragments and ash. Hydrocyclone fractionation of the screen long fibre fraction was split into a fine fibre fraction containing good bonding fibres and fines and a coarse fibre fraction with coarse low bonding fibres. The coarse long fibre fraction was then upgraded through refining to a strength level comparable to the good bonding fine fraction, but with an energy input of only 24 kWh/t calculated on the entire pulp. This selective refining of the coarse long fibre fraction resulted in an improvement of the total pulp strength by 20 % when the pulp fractions were mixed back together in the same proportions as they had been separated. Strength was improved further when the low bonding short coarse fraction with high ash content was removed.