Bitcoin Monday effect

Checked October 2026

The Monday effect buys bitcoin at the start of Monday and sells it at the end of Monday. Caporale and Plastun published it in Finance Research Letters in 2019. Backtoast ran it. The standard version made 8.2% a year at +0.60% a trade, but failed our test on trade frequency and outlier dependence.

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Bitcoin Monday effect

The rest of the week is cash. Monday is the UTC day, which is how the daily candles are cut, so in New York the trade runs from Sunday evening to Monday evening.

The other calendar rules here are the gold autumn effect and the turn of the month.

When it works

The edge is a calendar effect, and it comes and goes. It was strongest in 2015 in the original study and in the last six months of our run, at +2.14% a trade. It holds bitcoin one day a week, so it carries far less exposure than holding all week, which is why some traders use it as a lower-risk way in.

Origins

Caporale and Plastun counted 245 Monday trades from 2013 to 2017, 60% of them winners. The effect was significant over the whole sample but in only one year, 2015, on its own, and they didn't call it evidence of an inefficient market. Liu and Tsyvinski found no Monday effect from 2011 to 2018. The run is from late 2021 to September 2026.

The run is Backtoast's, from 29 October 2026, after costs.