The rule of thumb regarding sending an investor update email to your current investors is to do so on a monthly basis. Once a month is a reasonable interval giving you a chance to keep them informed about your work and assure them that their money is well-spent.
During early stages, things change pretty quickly. You might even want to share weekly investor updates in order to get much needed advice, recommendation or introduction faster. Sending updates once a week will accelerate establishing the relationship, especially if your investors are actively involved in your work.
If your company is in series A or B, the changes might not be as drastic as in the early stages. In such cases, you might opt for quarterly investor updates. However, bear in mind that it might have a negative side - your investors might not remember details as they usually have other startups that pitch at the same time. Your email may get lost among other updates.
Receiving regular data featuring both ups and downs of a company is the key to open conversation and timely support and help.
Ajim Capital is a pre-seed/seed fund investing into high-growth tech companies in Africa. https://ajimcapital.com/
