Roller and Roman blinds are two of the most popular made-to-measure styles, and they suit quite different jobs. The quickest way to choose is to decide whether you want the blind to disappear or to dress the window, because that is really the difference between them.
The basic difference
A roller blind is a single flat panel of fabric that winds onto a tube at the top. It is simple, minimal and takes up almost no space. A Roman blind is made from furnishing-weight fabric that gathers into neat horizontal folds as it raises, so it reads as soft furnishing - closer to a curtain in feel than a roller.
Look and feel
A roller is the neat, modern, understated choice: it lies flat against the glass and recedes into the window. A Roman is the warmer, more decorative choice: the folds add texture and softness, and the heavier fabrics carry pattern and colour beautifully. If the window is meant to be a feature, the Roman wins; if it is meant to be functional and quiet, the roller does.
Light control
Both come in light-filtering and blackout fabrics, so either can darken a bedroom or screen a living room. The practical difference is the stack: a Roman always gathers a band of fabric at the top of the window when raised, so it never clears the glass completely, while a roller winds away to almost nothing. On a short window that makes a roller the brighter option fully open.
Price and practicality
Rollers are typically the cheaper of the two, because they use less fabric and a simpler mechanism, and they are the easier style to get in a wipe-clean or moisture-resistant fabric for kitchens and bathrooms. Romans use more fabric and are lined and sewn, so they cost more and are better kept to drier rooms.
Which to choose
Choose a roller for kitchens, bathrooms, home offices, children's rooms and any window where you want a neat, affordable, low-fuss blind. Choose a Roman for living rooms, dining rooms and bedrooms where the window is part of the decorating scheme and a softer, dressed finish is worth the extra. Many homes use both - rollers in the working rooms, Romans in the living spaces.