As an additional point to those above, there wasn't even such a thing as common law marriage before the 1753 Act - I'd highly recommend "Marriage Law for Genealogists" by Professor Rebecca Probert, who's the world's leading authority on the history of marriage laws and practices. She's also written several academic articles on the law prior to 1753, and it's clearly one of her big bugbears that the idea that CLM existed before March 1754 has become the prevailing misunderstanding in the past few years. In actual fact, the only way of marrying before the 1753 Act was before an Anglican clergyman, and her research shows that only a vanishingly small number of couples lived together as husband and wife without going through a formal Anglican ceremony - her book's fascinating reading - highly recommended.