Monzo announced earlier this month that it is teaming up with fellow UK challenger bank OakNorth to offer cash ISAs to its clients; FT Alphaville did a little digging into this relationship and found that there is a significant difference between the savings rate earned at Monzo versus going direct to OakNorth, up to 40 basis points; Monzo is earning 20 basis points from each account and the remainder is being pocketed by OakNorth; Monzo has built a reputation on being transparent and customer friendly and the author questions whether practices like this are sustainable. Source.