Cost and construction
Framed runs cheapest: $190 to $500 once installed, since the metal frame does the structural work and lets the glass itself stay thin.[1]
Frameless spans a much wider band, anywhere from $300 up to $3,300, though the typical homeowner ends up around $530 to $1,391 once the job is done; a simple fixed panel sits near the bottom of that band and a custom curved enclosure sits near the top.[1]
The metal frame on a framed door does real structural work, supporting thinner, less expensive glass. Take the frame away and the glass itself has to get thicker while the hardware has to fit more precisely, which is most of why frameless costs more.
Day-to-day upkeep
A framed door's metal channels are the main upkeep headache: they collect soap scum, mineral deposits and mildew in corners that are awkward to reach with a normal cloth or brush.
A frameless door has far fewer channels and corners to trap grime, which is the main upkeep argument in its favor even though it costs more upfront.
The rule that applies either way
Framed or frameless doesn't matter for one rule: residential code flags any glazing within 60 inches, measured horizontally or vertically, of a shower or tub's water surface as a hazardous location, and glass installed there has to be tempered or another approved safety type regardless of style.[2]
Tempered glass carries a small permanent mark, typically etched or silkscreened in a corner, showing a Category I or II rating under the federal safety standard for glazing materials; Category II meets the higher impact-resistance bar and is what most residential hazardous locations call for.[2]
Choosing between them
A framed door makes sense when the budget is the main constraint or the opening is a standard size a manufacturer already makes, since it avoids the custom measuring and machining frameless glass needs.
A frameless door makes sense when the shower opening is non-standard, when a cleaner sightline matters more than upfront cost, or when the rest of the bathroom is being finished to a higher standard the metal-framed look wouldn't match.
Ordering and lead time
Framed doors, especially in standard sizes, are often stocked or built from standard components, so they can turn around faster than a frameless order.
Frameless glass is typically cut to your exact opening after a professional site measurement, which adds lead time upfront but avoids the gaps or trim pieces a slightly-off standard size can leave behind. Ask early in the process how long glass fabrication will take, since it's a common bottleneck that can leave the rest of a finished shower waiting on one piece.