Public sector workers across the county are striking today to protest against proposed changes to pension plans.
Schools, police, and council services are all likely to be affected.
Travellers using Stansted Airport have been warned to expect long delays at border control because UK Border Agency staff are among those striking.
108 schools confirmed to Essex County Council that they intended to close fully because of the strike action.
More than 300 schools have not informed the county council of their decision.
Marches were expected in towns across the county including Colchester, Chelmsford, Harlow, Southend.
An Essex Police spokesman said: "Essex Police put robust contingency plans in place on Wednesday, November 30 to ensure that critical services were fully maintained throughout the day.
"As of 3:30pm today there have been no reported problems and all emergency and non emergency calls have been answered and responded to in the most appropriate way.
"Essex Police estimates that under 5 per cent of support staff (including PCSOs) took part in the industrial action.
"Across the county Essex Police has worked with partner agencies to ensure minimal disruption to anyone not taking part in a protest and going about their daily business. At the present time there are no strike-related incidents to report."
Councillor David Finch Deputy Leader and the Cabinet Member for Finance and Transformation Programme, said: “Today’s National Public Sector strike has had a minimal impact on Essex County Council’s services, there were no issues in our adult or children’s social care areas, our libraries were all open and our highways and transport services are all running as usual, although 2 mobile libraries did not go out and a handful of adult evening classes will not take place tonight.
My impression from being in County Hall today is that most employees attended for work as normal.
Of course we would have preferred no industrial action at all, but we are pleased that our employees as well as local and regional level trade unions have taken a measured approach”
Latest list of closures