I fixed this for me, using a fixed container height:

<Input containerStyle={{ height: 55 }} />

Shouldn't all elements simply have no padding/margin at all?

Agreed. Wish there was a way to easily remove all default styling.

There's an annoying bottom margin you can't get rid of for Input. Not sure why it's there.

FWIW, here's the styling I've applied at the theme-level to the BaseInput in my component library (which implements Input from react-native-elements). It overrides (afaik): all height, margin, and padding-related defaults for Input:

inputContainerStyle: {
  borderBottomWidth: 0,
  height: undefined,
  paddingVertical: 0,
  paddingHorizontal: 0,
},
rightIconContainerStyle: {
  paddingLeft: 16,
  paddingRight: 0,
  paddingTop: 0,
  paddingBottom: 0,
  marginVertical: 0,
  marginHorizontal: 0,
  height: undefined,
},
leftIconContainerStyle: {
  paddingRight: 16,
  paddingLeft: 0,
  paddingTop: 0,
  paddingBottom: 0,
  marginVertical: 0,
  marginHorizontal: 0,
  height: undefined,
},
inputStyle: {
  minHeight: undefined,
  paddingVertical: 0,
  paddingHorizontal: 0,
},

@wkoutre It looks like this margin is still there for me even with your changes. https://snack.expo.dev/@nmorrell/jealous-cereal . It looks like containerStyle lets us remove the horizontal margins, but the bottom margin stays regardless. The fixed container height change suggested above does limit the margin but it seems it should just be controllable via containerStyle.

@wkoutre That is very helpful! Thanks!

The margin on the bottom of the Input is caused by inbuilt error message component which reserves some space. You can disable it with: renderErrorMessage={false}

The margin on the left and right of the Input is caused by the default 10px horizontal padding on the container. You can disable it with containerStyle={{ paddingHorizontal: 0 }} but you might not want to.

In my case that padding was confusing me because it looked like margin instead because I'd set a background colour on the style, whilst the containerStyle had no background making the transparent container look like margin.

To fix the issue I moved my backgroundColor from the style to the containerStyle.