This research contributes to the assessment of the potential for carbon dioxide (CO₂) sequestration in poplar plantations, through applying regression models of total and annual sequestration as related to stand age. The study was carried out in northern Serbia, in plantations of Populus ×euramericana (Dode) Guinier clone I-214. Based on the measured data obtained during the field research, a modeling framework for quantifying carbon (C) sequestration in forest ecosystems (CO2FIX version 3.1) was used to calculate the total carbon stored in fresh (aboveground and belowground) biomass, in soil organic matter, and in wood products. Four regression models were created as a part of the research: (i) total C sequestration model, (ii) total CO₂ sequestration and carbon credit (CO₂e) generation model, (iii) annual C sequestration model, and (iv) annual CO₂ sequestration and annual carbon credit generation model. The stand-level research results indicated that the total sequestration of C for a 30-year production cycle was 78.58 t C·ha⁻¹, while the average value for all years of a 30-year production cycle was 44.02 t C·ha⁻¹. The average annual sequestration of C for all years of a 30-year production cycle was 2.62 t C·ha⁻¹·year⁻¹, while the average annual sequestration of CO₂ or the average annual changes in CO₂ stocks for all years of a 30-year production cycle was 9.60 t CO₂·ha⁻¹·year⁻¹.