Catalytic methanation is one of the possible process routes for production of biomass-derived synthetic natural gas (BioSNG). Firstly, the feedstock of biogenic origin (e.g., woody biomass or other biogenic residues) has to be converted into purified syngas for subsequent CH4 synthesis. Dual fluidized bed (DFB) steam gasification is a promising technology for this aim, as it offers the possibility of producing H2-rich, low-N2, product gases, as opposed to air-blown fixed bed gasifiers. The syngas provided by this technology is in principle suitable for further methanation although gas conditioning (addition of H2 and/or H2O) may be necessary due to increased risk of catalyst deactivation by formation of solid carbon (catalyst coking). Previous experience shows, that fluidized bed methanation can manage this risk to some extent, which is why it is the technology of choice for SNG synthesis at TU Wien. Typically, nickel-based catalysts are used for methanation purposes. Generally, the overall exothermic reaction heat can easily be dissipated and maintained via cooling of the fluidized bed. Therefore, the risk of catalyst deactivation due to thermal stress (e.g., catalyst sintering) can be minimized. The amount of required gas conditioning can be calculated in advance based on thermodynamic equilibrium (TDequ) calculations or estimated based on, e.g., H2:CO ratio in the syngas. In this study, methanation experiments (parameter variation study and long-term operation) were performed in a 10 kWth fluidized bed methanation test rig with syngas obtained from the 1 MWth advanced DFB gasifier located at the Syngas Platform Vienna. The gas was cleaned on site using a modified gas cleaning process route and then stored in gas cylinder bundles for later use – such as in fluidized bed methanation at TU Wien. The parameter variation was performed with gas conditioning to a varying extent, and varying methanation operating parameters (OP: methanation temperature, weight hourly space velocity). The results of the parameter variation were interpreted in context of distance to the respective TDequ, and validated and evaluated via process simulation in IPSEpro. A promising OP – in terms of an expected good trade-off between technical and economic feasibility– was then used for subsequent long-term operation. For evaluation of potentially occurring catalyst deactivation, a combination of methods was applied: 1) Chemical analyses of catalyst samples before/after methanation tests and 2) observation of gas composition during long-term operation with fixed OP. As a result, the suitability of selected OP can be determined in terms of process stability and conclusions about the performance of the proposed gas cleaning route upstream can be drawn. The experimental results show significant influence of the amount of gas conditioning, methanation temperature (320-360 °C) and weight hourly space velocity (WHSV, 1.1-1.5 Nl·gCat-1·h-1) on the raw-SNG composition. For example, the increase of water content from 10 to 45 v.% leads to a relative decrease of CH4 and CO concentration by 10% and 54% respectively, and to a relative increase of H2 concentration by 148%. This corresponds to reduction in CH4 productivity by 42% (0.33 vs. 0.19 Nl·gCat-1·h-1). Thus, elevated risk of carbon deposition was accepted for long-term operation with water content of 20 v.% and no additional H2. However, no significant carbon deposition was detected by conducted chemical analyses after approximately 16 h of operation even though a slight change in CH4 and H2 concentration was visible during operation. In Austria, the specifications of the ÖVGW directive G B210 have to be met for feeding renewable gases into the natural gas grid. Since the product from fluidized bed methanation is not yet suitable for this purpose, certain gas polishing and separation steps have to be performed beforehand. This SNG upgrading was not investigated experimentally in this study, but is to be estimated through mass and energy balances of the entire proposed biomass-to-SNG process chain via process simulation in IPSEpro. Based on these balances, further investigations via, e.g., life cycle assessment (LCA) can be performed for further determination of this technology.