Sodium, one of the most widespread metals in the earth's crust, can be mined virtually everywhere and holds great promise as an electroactive material batteries to compete with commercial lithium-ion batteries in terms of price and availability. However, sodium, unlike lithium, cannot be intercalated in graphite and therefore there is a need to develop sodium anodes from alternative abundant and low-cost materials. Here we show that one-step carbonisation of melamine–terephthalaldehyde mixtures, both low-cost chemicals available on an industrial scale, yields carbons with promising properties as anodes for sodium-ion batteries. The produced materials apparently contain a large number of small pores, unreachable to gas molecules, which can store sodium (in a quasi-metallic state) as Na(0). The carbon shows plateau behaviour above and below 0 V vs. Na/Na⁺, with a capacity of up to 170 mA h g⁻¹ until bulk sodium plating occurs. Additionally, for 60 cycles the carbon shows high stability, exhibiting low degradation and efficiencies close to 100%. This report is a first step towards the use of nitrogen-doped carbon materials from low-cost, industrially widespread precursors as anodes for sodium-ion batteries.