Problems on the railways and with flooding have brought disruption to the postal service in Oxfordshire.
Royal Mail spokesman Richard Hall said: "We are experiencing difficulties with the Rail disruption, which has been compounded by the weather.
"Some mail coming into Oxford for delivery is being delayed.
"The large majority that is missing the first delivery is picked up by the second delivery. Parts of rural Oxfordshire only have one delivery, and unfortunately, that mail is arriving a day late.
"We are concerned about the Christmas post because Railtrack are warning disruption might continue right up until Christmas. The message is always post early."
He advised customers to post cards for second class on December 18 and for first class by December 21 at the latest.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules hereComments are closed on this article