Time series analysis of Nigerian monthly Inflation Rates (INFL) Data is done. It is observed that it is seasonal. Based on its autocorrelation structure as depicted by the correlogram, the multiplicative seasonal autoregressive integrated moving average (ARIMA) model, (1, 1, 0)x(0, 1, 1)12, is fitted to the series. The model is shown to be adequate and the 2012 forecasts are obtained on the basis of it. These forecasts are shown to agree closely with the observations.