It will cost more to send post from Guernsey from 5 January.
Local stamps will rise by four pence to 56p, while postage to the UK will go up by 8p to 87p.
Rates to Europe and the rest of the world, and to send parcels to the UK are also rising:
• The price of a Letter to Europe will rise by 11p to £1.21
• The price of a Letter to the Rest of the World by 15p to £1.50
• A small 250g parcel to the UK will rise by 40p to £4.38
• A small 500g parcel to the UK will rise by 45p to £4.93
Guernsey Post says it has to meet demands by Royal Mail and substantial hikes in transportation costs.
"We have done and will continue to do everything we can to improve our efficiency, but even with these changes the company will move into a short term loss-making position for the first time in 11 years.
Our trading position has become much more challenging in the context of high inflation, and some unprecedented increases in costs from our suppliers. We have a clear plan and this loss-making position will be short term as we work on ways to improve our efficiency. The most significant change we are making is the investment in parcel sorting automation which will be installed next year.” - Boley Smillie, Guernsey Post Chief Executive.
Last month Guernsey Post announced an operating profit of £1.6 million in the financial year to the end of March as it set out its investment plans including a £1.8m piece of kit for sorting parcels more quickly.

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