If I can give three advice, the first thing is not to forget about the staff. Internal communication is at least as important as the external one. Make sure your own employees are up to date with all the information available. Then they feel safe and involved. If the crisis goes on for a long time, they will also be your messengers.
Secondly, keep a steady flow of information. Even when there is nothing new to tell, communicate it anyway. You can present when the next information will come or when you will be able to answer a particular question. It helps to create security for your listeners or visitors.
Finally, I think you should think about your target groups. We are usually good at target group thinking in the everyday work, but it is sometimes forgotten in crisis. Who are your target groups, how do you best reach them and what do they need? Differentiate your communication to be as effective as possible in relation to the target group. And how is your relationship with the different target groups? Do they trust you? Have they been in similar situations before? As usual, the more detailed knowledge you have about the different target groups, the more effective your communication will be.
I absolutely have to choose speed. Being quick with information is one of the cornerstones of crisis communication. If you are quick in the beginning, space is created to help those who have special needs.
We do not have a special channel in crisis, but use almost the same channels as usual. That is, if, for example, you find it difficult to read or have any other disability, you are primarily referred to our phone service. There you get the opportunity to talk to a person. We have well-established routines to always keep the phone service up to date on everything that happens at the Swedish Tax Agency. Most crises that are affecting individuals, such as with Covid19, are quite slow. Then we assess that there is time to call the phone service or to visit a service office.