on account of

• on something's account
• on account thereof (formal)

on account of

1. On behalf of the (monetary) account of; (idiomatic, originally figuratively) for the sake of.
   • 1842 August 29, Treaty of Nanking:

     […] and His Imperial Majesty further agrees to pay to the British Government the sum of Three Millions of dollars, on account of debts due to British subjects by some of the said Hong merchants (or Cohong), who have become insolvent, and who owe very large sums of money to subjects of Her Britannic Majesty.

2. (idiomatic) Because of, due to, owing to.
   • 1991, Stephen Fry, The Liar, p. 26:

     ‘My brother... is at Radley, on account of my parents thinking it a bad idea to have both of us at the same school.’
     ‘On account of your being twins?’ said Adrian.
     ‘Right, on account of my mother OD-ing on fertility drugs.’

• When the object of this preposition is brief and animate, the alternative construction on someone's account is often used instead. If the object is a personal pronoun, that construction is more common; for example, on my account is more common than on account of me.
• Similarly, on that account, using that as a determiner, is more common than on account of that.

on account of

1. (colloquial) On account of the fact that: because, since.
   • 1998, Bill Bryson, A Walk in the Woods: Rediscovering America on the Appalachian Trail, Broadway Books (1999), →ISBN, page 213:

     […] I had a pretty good notion of the weather conditions generally, on account of I was out in them.

   • 1999, Craig S. Womack, Red on red: Native American literary separatism, University of Minnesota Press, →ISBN, page 216:

     Truth is I was the kind of fellow who people would run away from when they seen me coming on account of I was so full of facts and names and places and families I had to tell about.

   • 2015, Bill Bryson, The Road to Little Dribbling: More Notes from a Small Island (page 84)

     After that, I resumed walking, on account of it involves little contact with strangers.