They blame a poor response to a recent share issue, drop in season ticket sales and Southend's refusal to pay £125,000 for Jamal Campbell-Ryce for the problem.
In a stark message to fans, shareholders, players and staff, chairman Peter Ruchniewicz said: “We are sorry to have to tell you that the club’s financial position has entered a critical phase and there is the very real prospect that the club will be advised to cease trading within the next few weeks.
“Heaven forbid, but if the club does cease trading it is likely to go straight into liquidation – it seems unlikely it could go into a formal administration given its limited resources and the level of funds and assets required.
"This would mean that the club would go out of existence, a thought too dreadful for any of us to contemplate but nevertheless a very real possibility."
The club have held talks with the PFA and major creditors, and have launched a Save Our Millers campaign.