While most beach umbrellas can double as patio umbrellas, this largely depends on the model you get. Patio umbrellas use weighted bases or tables with holes to keep them in place so, to do a good job, a beach umbrella must fit in the base well.
Also, a beach umbrella generally has a smaller canopy diameter than a patio umbrella, which can be a problem if you need to shade a dining table with several chairs. Lastly, beach umbrellas are often more brightly colored, so they may not blend well in the patio décor.
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