Key difference: Though the prepositions ‘beside’ and ‘besides’ do not differ that much in their spellings, they have different meanings. The word ‘beside’ is used as a preposition while ‘besides’ is used as a preposition as well as an adverb.

Often, the words ‘beside’ and ‘besides’ confuse the writers. In grammar, ‘beside’ is used as a preposition, whereas ‘besides’ is used as either an adverb or preposition. The single letter ‘s’ is only the difference in their spellings, but the words also differ in their usages.

The word 'beside' reflects the meaning such as something which is close to or next to. Another meaning for the word in Middle English was “outside”. In the modern usage, this term is used to highlight something which is either 'next to something" or is being used to compare something side by side.

For example:

• Jerry’s restaurant stood beside the Central Park.
• Grandpas always like to sit beside Grandmas.
• An idea that seems quite valuable beside the others.

'Besides' reflects the meaning such as to introduce something in a conversation. It can also be used as a synonym for except or excluding. In the preposition form, it means in addition to or apart from; else in adverb form it means as well or furthermore. It is also used to introduce a noun clause.

For example:

• As preposition: What are you studying besides Mathematics?
• As adverb: He was scruffy and badly prepared. Besides, he turned up late for the presentation.

• As a noun clause: Besides what he said, we must consider what she said.

Comparison between Beside and Besides:

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