Heri zote
CORRECTION; This not a phrase that would occur in Swahili. You don't say "best" wishes in Swahili but rather wish someone good luck or a blessing. so the answer to the question is this:
Nakutakia (nakuombea) heri. I want (pray) the best (i.e., a blessing) for you.
best wishes
There are times when it is, and times when it is not.
In Bulgarian, you can say "най-добри пожелания" which translates to "best wishes."
best regards
We say 'dymuniadau gorau.'
Parabens
You say "Best wishes" in Yoruba language of the Western African origin as "Nko rere fun e".
You say "Accept my best wishes" in Yoruba language of the Western African origin as "Gba nkan rere timo fefun e".
You say memorize in Swahili like this: kukariri
You can say "Nakukosa" in Swahili to mean "I miss you."
In Swahili, you can say "salamu za dhati" to mean 'best regards'.
The Swahili word is 'Na'