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Stratospheric profiles of methane (CH₄) and carbon dioxide (CO₂) have been derived from solar occultation measurements of the SCanning Imaging Absorption spectroMeter for Atmospheric CHartographY (SCIAMACHY). The retrieval is performed using a method called onion peeling DOAS (ONPD), which combines an onion peeling approach with a weighting function DOAS (differential optical absorption spectroscopy) fit in the spectral region between 1559 and 1671 nm. By use of updated pointing information and optimisation of the data selection as well as of the retrieval approach, the altitude range for reasonable CH₄ could be broadened from 20 to 40 km to about 17 to 45 km. Furthermore, the quality of the derived CO₂ has been assessed such that now the first stratospheric profiles (17–45 km) of CO₂ from SCIAMACHY are available. Comparisons with independent data sets yield an estimated accuracy of the new SCIAMACHY stratospheric profiles of about 5–10 % for CH₄ and 2–3 % for CO₂. The accuracy of the products is currently mainly restricted by the appearance of unexpected vertical oscillations in the derived profiles which need further investigation. Using the improved ONPD retrieval, CH₄ and CO₂ stratospheric data sets covering the whole SCIAMACHY time series (August 2002–April 2012) and the latitudinal range between about 50 and 70° N have been derived. Based on these time series, CH₄ and CO₂ trends have been estimated. CH₄ trends above about 20 km are not significantly different from zero and the trend at 17 km is about 3 ppbv year⁻¹. The derived CO₂ trends show a general decrease with altitude with values of about 1.9 ppmv year⁻¹ at 21 km and about 1.3 ppmv year⁻¹ at 39 km. These results are in reasonable agreement with total column trends for these gases. This shows that the new SCIAMACHY data sets can provide valuable information about the stratosphere.