Welsh information at 2016 assembly election 'unsatisfactory'
Welsh language information for assembly election voters was unsatisfactory, the Welsh language commissioner has said.
Meri Huws's report said while there had been "clear progress", the availability of Welsh registration forms continues to be "insufficient".
Three councils only provided guidance in the English language.
She said she expected officials to improve the position before the council elections in May.
The commissioner's review considered the availability of Welsh language information for voters before the assembly and police and crime commissioner elections, held last May.
It also analysed the way Welsh was used when results were declared at individual counts.
According to the report there has been "clear progress in terms of election documentation and forms with all registration forms now available in Welsh".
However the availability and accessibility of those forms "continue to be insufficient".
The research found examples where the information had to be searched in English first, and cases where links provided on Welsh web-pages would direct the reader to documents written in English.
The work also found that whilst every local authority website offered bilingual information in 2015, by 2016 three councils only provided guidance in English.
However Ms Huw suggested that, on the whole, there had been an "improvement" following the general election held the previous year.
On declarations, the commissioner found "many cases" where the Welsh declaration was "less comprehensible" than the English declaration.
Ms Huws said: "Reviewing the 2015 general election arrangements, it became clear that there was a considerable weakness in the way the Welsh language was treated.
"It's encouraging that the situation had improved by 2016, and that all forms were available in Welsh.
"But it remained unsatisfactory that people had to persevere and make a special effort to access the forms and information in Welsh."
The Electoral Commission, which offers support to Returning Officers, said it "welcomes" the report.
Rhydian Thomas, head of The Electoral Commission in Wales added: "It's vitally important that voters in Wales are able to take part in the democratic process in the Welsh language."