Explanation
In Spain, unlike in many Middle Eastern or South Asian cultures, there is no stigma attached to eating with the left hand. Spanish dining etiquette focuses on using utensils properly—knife in the right hand, fork in the left—but if you switch hands or eat finger foods with your left, it is perfectly acceptable. The left-hand taboo is not part of Spanish custom, so you need not worry about causing offense.
Local Tip
Just focus on using your utensils correctly and avoid eating with your hands for main courses unless it's tapas like patatas bravas or croquetas.
How it compares elsewhere
Eating with the left hand is considered unclean, as the left hand is traditionally used for hygiene purposes.
The left hand is reserved for bathroom hygiene; always eat and pass food with the right hand.
Strict Islamic etiquette forbids using the left hand for eating or offering food.