In Castilla y León, the recent election polls performed moderately well, accurately predicting a win for the Popular Party (PP) but without giving them an absolute majority. The overall average error among polls was 1.7 percentage points, slightly better than their historical accuracy rate of 2 points in Spain. Notably, Sigma Dos and GAD3 yielded more precise estimates, with errors of 0.8 and 1.1 points, respectively.

The average of the polls effectively captured the general balance between the left and right parties; the left parties received 34% of the vote compared to the predicted 35%, while the right parties garnered 56%, exactly as forecasted. However, the individual performance of parties within these blocs was less accurate. The polls underestimated the Popular Party by 2.5 points and the Socialist Party by 2.1 points, while they overestimated some leftist factions. This trend of overestimation toward the left has been a recurring issue with Polito Tezanos' surveys, as he has misjudged the left side in 43 of 44 electoral instances.

The findings suggest that while polling has its merits in anticipating electoral outcomes, the consistent bias in favor of leftist parties, especially in the case of the CIS under Tezanos, raises questions about the reliability and overall impact of these surveys. As political landscapes evolve, it is crucial for polling organizations to address these discrepancies to maintain credibility and offer voters a more balanced view of election forecasts.