Only priority orders are being fulfilled until Thursday as stocks are running low at the Scottish Fuels terminal in Stornoway.
It is understood a sea tanker full of heating oil, petrol and diesel is on its way from a refinery at Immingham. She is scheduled to dock at Stornoway until Wednesday.
She will pump oil products into the pipeline in Stornoway harbour, which will replenish the depot's huge storage tanks.
Until then, Scottish Fuels customers may be asked to accept a reduced order.
If customers have sufficient supplies to tide them over until the end of the week, they may be asked to take a delayed delivery.
A spokeswoman for GB Oils, the parent company of Scottish Fuels, stressed the depot was focusing on honouring urgent orders for the coming days but had sufficient fuel and had not run out.
One island retailer station desperately hoping to get a full order today is the Back Filling Station, which ran out of diesel after a rush of motorists when it slashed its forecourt prices.
Though the station has ditched Scottish Fuels, its new wholesaler takes oil from the same depot.
For a number of weeks recently islanders from North Uist to Eriskay faced fuel rationing after shortages on the island.