Is that something expected in Northern Ireland & the Irish Republic? I just want to be sure to follow customary etiquette there.
In two trips to Ireland, we never tipped at a B&B. However, we brought little keepsakes (pins, books, etc. from representative of our home state of Virginia) to give to the ladies of each establishment as a token of our thanks for their hospitality. In every case, they were taken aback by this gesture and we left on very fond terms.
I have never tipped at a B&B. I do sometimes send a thank you card afterwards if the B&B was particularly nice.
We have visited many Irish B&Bs. No tipping was involved. Often, we did pay in cash which was very much appreciated. We were always respectful of their home and we worked at complete communication with our hosts about arrival times, etc. Its an attitude thing; you are not family but you have a little more than a strictly business relationship.
When we stay at hotels/B&Bs we often leave a tip in the bedroom for the chambermaid, if there was one. That is of course if they did a good job, it not usually a well paid job.
I don't generally tip in a B&B.
Paying in cash is like giving them a tip, that saves them the transaction fees for running a credit card.
When we've been well treated, we like to leave a chocolate bar wrapped in a piece of paper with Thank you written on it.