YES - there is a square slip pocket on the back.
I went into MK Boutique today and made a beeline for this bag (in elephant, which is a muddy sepia dark taupe). I was struck by the small-ish size of the bag but it's still a very, very practical size. It's just compact compared to what I typically carry or gravitate towards.
There is some org inside, a zip pocket and another slip pocket. Closure is secure with two strong magnets. I love the thick pebbled leather more than smooth buffed calf leather (Casey large same colour). Actually, I have a Chloe Marcie in Ash which is the same colour as this. I should carry my Marcie Ash and do a sbs comparison - maybe the Chloe Ash is a tad darker.
The SA told me there are only 4 of these bags in Canada - they are really limited worldwide and I think she said 8 in the USA?! But I'm not sure I heard her right - was half listening. Dang it...I was tempted but I should not be sporadic here...I've done that way too much when it comes to handbags. I still own more handbags than I can ever imagine carrying.