We had close family round at the house for cake and nibbles plus got ds a helium balloon.
So maybe £20 for everything - cake, balloons, nibbles and a cake.
His christening was more expensive than his first birthday (he was christened at 4 months old). More people came, we had a cake made and we bought him a special outfit so in total probably £100 altogether.
Planning to have the family tea party for his second birthday too and will probably go for a nice day trip.