Bio-oil is a complex blend of oxygenated compounds, such as acetic acid, hydroxyacetone and phenols, and is produced from the fast pyrolysis of raw biomass. A raw bio-oil produced from pine woodchips was co-processed with standard gasoil and tested in a 150 kg/h fluid catalytic cracking (FCC) demonstration-scale unit. The bio-oil was cracked into valuable products, such as gasoline and LCO, with similar product yields obtained from the base FCC feed when up to 10% bio-oil was used. However, some deterioration was observed when 20% bio-oil was added. C-14 isotopic analyses were performed to determine the renewable carbon content in the FCC liquid products. When 20% bio-oil was co-processed, the renewable carbon content in the gasoline cuts varied between 3% and 5%. For 10% bio-oil in the feed, 2% renewable carbon was obtained in the total liquid product. Large amounts of phenolic compounds were detected in the naphtha produced by the FCC. The FCC carbon efficiency, which is defined as the amount of carbon in bio-oil converted to carbon in the total liquid products, was approximately 30%, well above the values found in the literature for FCC bio-oil upgrading (15%-.20%) when using laboratory scale units. (C) 2014 Elsevier B.V. All rights reserved.