Is it possible to change a UIButtons background color?

I have a different approach,

[btFind setTitle:NSLocalizedString(@"Find", @"") forState:UIControlStateNormal];    
[btFind setBackgroundImage:[CommonUIUtility imageFromColor:[UIColor cyanColor]] 
        forState:UIControlStateNormal];
btFind.layer.cornerRadius = 8.0;
btFind.layer.masksToBounds = YES;
btFind.layer.borderColor = [UIColor lightGrayColor].CGColor;
btFind.layer.borderWidth = 1;

From CommonUIUtility,

+ (UIImage *) imageFromColor:(UIColor *)color {
    CGRect rect = CGRectMake(0, 0, 1, 1);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context, [color CGColor]);
    //  [[UIColor colorWithRed:222./255 green:227./255 blue: 229./255 alpha:1] CGColor]) ;
    CGContextFillRect(context, rect);
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return img;
}

Don't forget to #import <QuartzCore/QuartzCore.h>

I assume you're talking about a UIButton with UIButtonTypeRoundedRect? You can't change the background color of that. When you try changing it's background color you're rather changing the color of the rect the button is drawn on (which is usually clear). So there are two ways to go. Either you subclass UIButton and overwrite its -drawRect: method or you create images for the different button states (which is perfectly fine to do).

If you set the background images in Interface Builder you should notice that IB doesn't support setting images for all the states the button can have, so I recommend setting the images in code like this:

UIButton *myButton = [UIButton buttonWithType:UIButtonTypeCustom];
[myButton setBackgroundImage:[UIImage imageNamed:@"normal.png"] forState:UIControlStateNormal];
[myButton setBackgroundImage:[UIImage imageNamed:@"disabled.png"] forState:UIControlStateDisabled];
[myButton setBackgroundImage:[UIImage imageNamed:@"selected.png"] forState:UIControlStateSelected];
[myButton setBackgroundImage:[UIImage imageNamed:@"higligted.png"] forState:UIControlStateHighlighted];
[myButton setBackgroundImage:[UIImage imageNamed:@"highlighted+selected.png"] forState:(UIControlStateHighlighted | UIControlStateSelected)];

The last line shows how to set an image for the selected & highlighted state (that's the one IB can't set). You don't need the selected images (line 4 & 6) if you're button dosn't need a selected state.

This can be done programmatically by making a replica:

loginButton = [UIButton buttonWithType:UIButtonTypeCustom];
[loginButton setTitleColor:[UIColor blackColor] forState:UIControlStateNormal];
loginButton.backgroundColor = [UIColor whiteColor];
loginButton.layer.borderColor = [UIColor blackColor].CGColor;
loginButton.layer.borderWidth = 0.5f;
loginButton.layer.cornerRadius = 10.0f;

edit: of course, you'd have to #import <QuartzCore/QuartzCore.h>

edit: to all new readers, you should also consider a few options added as "another possibility". for you consideration.

As this is an old answer, I strongly recommend reading comments for troubleshooting