Ted Duggan is still waiting his weekly payments
The government's public accounts watchdog has confirmed to BBC News Online it will be investigating delays in the launch of new tax credits.
The news comes amid growing calls for compensation from people who have not received payments in time.
A number of BBC News Online readers say they are becoming increasingly concerned about their financial situation.
The National Audit Office (NAO) said it will be investigating the way the system was introduced last month.
The NAO will unveil its findings this Autumn, as part of its annual audit of the Inland Revenue.
A spokesman said: "We are keeping a close eye on the topic with the Inland Revenue at a senior level and we will report on the start up problems with the new tax credits as part of our standard report".
The NAO scrutinizes public accounts and ensures tax payers get value for money out of public services.
Many people depend on the tax credit money to pay for their childcare, and supplement their incomes.
My money has just about dried up now
The introduction of tax credits is a key part of the government's welfare to work programme, and has meant many people have been able to return to work.
Chas Roy-Chowdhury, Head of Taxation at ACCA, said: " At the very least there should be proper financial compensation for this mistake.
"The current taxation system is, however, a 'one-way street' in terms of fines and interest charges for late payment of monies due.
"Perhaps there should be a similar system, if the Revenue is late."
Ted Duggan contacted BBC News Online about the problems he was having in receiving his tax credit payments more than two weeks ago.
But he is still waiting for his payment, despite receiving his notification letter on 17 April.
The delay means Mr Duggan, 49, a widower and father-of-two from Coventry, is facing another bank holiday weekend with little money.
His last payment under the old-style tax credit was received five weeks ago, and he is now owed about £600.
"I checked my bank twice today. They sent me the notification but haven't got even back to me. it is so frustrating. My money has just about dried up now."
Mr Duggan says he still cannot get through to the helpline.
"I just don't know what to do now. It is just so frustrating I don't know who to speak to."
According to other BBC News Online readers, the government may not meet its payment deadline of 2 May.
Two thirds of all claimants are due to receive their direct payments of tax credits every four weeks.
The government recently said: "If they sent their claim to the Inland Revenue by the end of January, and there are no outstanding enquiries, they can expect to receive their first tax credit payments no later than 2 May."
Yasmin Ramikie, a reader, has written to say: "Well, May 2nd is here and still no money. I have absolutely no money..How can I afford to pay for my daughter's childcare, our rent, food etc. This system is a farce."
Meanwhile, Anna from London, writes: I have yet to receive any payment, and I am beginning to feel very desperate. It takes days to get through, and each time I do, I get a different story form the operatives.."
In a written statement earlier in the week, the government said: "The vast majority of those opting to be paid weekly and who claimed by the end of January should have received their money already."
The government has said there are a "tiny minority of cases where a payment is due and has not been received".
It said claimants could visit their local Inland Revenue office.
"Local offices can check the status of a claim and, where appropriate, can arrange an emergency payment of tax credits."
Have you received your payments? Are you still waiting? What should the government do about it? Should it offer compensation?
Well they managed to get some money to me! But it is the wrong amount!! This means I will now have to work a six-day week to make up the shortfall. Of course overtime will then affect the amount of tax credits I get in the future. Basically the Inland Revenue is onto a winner, if they don't pay they gain interest on the money and because of late payments it means they will not have to pay out so much to those of us whose overtime will affect the claim.
Instead of having a tax-free allowance and then expecting those on low incomes to fill in extensive forms, which are then checked by an army of pen-pushers, who then pass the details on to another army of bureaucrats who then give some of the tax back assuming they pass all the qualifiers, why not cut out the middleman and increase tax coding? The US method is so simple - for every child you get an extra $3,000 or so of tax-free allowance.
John B, UK
Who is held responsible for the high rates of credit card interest I am paying?
I have still not received any notification of how much tax credit I will get, nor any money. As a self-employed mother with a husband who cannot work, I will rely on this money to feed my family. Who is held responsible for this and what compensation will I receive for the high rates of credit card interest I am paying? The helpline is constantly engaged and I don't have time to chase this on my own any more. Please let me know what is being done about this.
Kate Niewoudt, Britain
We now have our notification and are receiving tax credits on time. But we were delayed and clogged up the system because the IR insisted on basing our claim on out-of-date information, i.e. earnings April 2001-2002. We then had to ask for a new notification based on current earnings to get the claim rectified. How many like us had to claim twice, despite warning the IR that this would be so? We should have been allowed to submit correct information from the start.
I applied for CTC online well before the recommended 31st Jan deadline. The process although not overly complicated required information that is usually stuffed at the bottom of a forgotten drawer, however, once the info is supplied there seemed to be no problems. The only issue I had with the online system is that the receiving party did not send a confirmation e-mail to me to say that they are processing the claim. I did receive a letter many weeks later to sign and send back to confirm who I was. It would be interesting to find out if there was more problems with sending in cumbersome paperwork rather than online. By the way what I gained in CTC was duly taken back by Mr Brown in the form of his stealth taxes on National Insurance! Was there any point in applying for CTC?
I've been trying for the past two weeks to get through on the helpline. I applied online mid January and haven't had any correspondence yet. My local tax office informed me last week that I would receive my letter by today (2/5/2003), but I haven't! My partner did however check her bank account today and discovered that a payment had been made.
Mark Parter, Scotland
I applied by internet. I am now owed £720. My local tax office promised to contact the tax credit Dept and today got a call from the Dept. My internet application was not received. I have to re-apply and lose all my back-dated payment. I have telephoned the helpline every day since April 8th but they could never tell me (and it seemed - didn't want to find out) if my form was received.