tenia or tuve
I had plans.
Thank you , but it was already answered by the time that I posted.
As others said it depends on the context, whether the action is viewed as momentary (the duration is defined with ending or beginning times mentioned) or completed (perfected) in the past or ongoing in the past (habitual) or could be still happening in the present. (not perfected or imperfect)
Tuve planes (once in my life or last year)
Tenía planes (sounds like a repetitive action in the past)
Could you give us more context please?
With just this sentence, I would have to go with "Tuve planes." because it sounds like you might just "had plans" and maybe they got canceled. Benz, you are correct in saying more context is better. Eddy, it's always better, right?!! Now if somebody is "blowing" you off and not showing up for the plans that were made (you see this is what I mean as well)... The more context the better.