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Tax Return Attachment File Size

Tax Return Attachment File Size

I have used Iris to generate an amended electronic partnership self assessment return for the 2010/11 tax year.  I consider it necessary to attach a PDF with a file size of 3.5Mb, which is clearly within HMRC's 5Mb size limit. 

Having tried and failed twice to submit this return I am told by Iris that in practice it is not possible to transmit files exceeding 1.5/2.0Mb because the internet connection drops out.  They are saying this issue is with HMRC, not my own ISP.

Has anyone come across this issue before?




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18th Jun 2012 12:18

something in the back of the grey matter

says that if you make a note in white space and then send the attachment via snail mail within 30 days of the submission it will count as part of the original.

Anyway it is only June so why not submit the whole thing on paper and save yourself time and grief!!!

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18th Jun 2012 16:37

Not sure if its the current scenario

It used to be the case that the HMRC system added a substantial amount to the file size by including the return itself. Depending on the size of the return the practical limit used to be around 1.9MB - using CCH rather than Iris.

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18th Jun 2012 18:53

Check your PDF settings

Hi Tim - you don't say what is in the attachment but unless it's a scan of the Sunday Times (in colour) there must be a way to reduce 3.5Mb.  As I tell clients who send me 10Mb scans of an invoice, "would you post me a paper copy in a parcel with a brick"?

I've asked Iris on a number of occasions what settings they use and whether they could incorporate even the simplest of choices but they ignored me.  A good example was a 40 page SA tax return last year that Iris created as a 2.4Mb PDF but when it was joined with 10 pages of cover letter, schedules & notes the 50 page PDF pack was just 640Kb.

We use Adobe Acrobat but whatever sort of PDF creator you have,or get (and there are loads around) play around with the settings as say a converted 2 page word doc should be no more than 50-60 Kb.



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19th Jun 2012 12:16

Thanks so far

In response;

The Innkeeper - What you say is a solution, but why can't HMRC give us what is advertised on the tin?

mn2taxhbj  - Iris haven't given me this specific explanation, but what you say sounds plausible

Paul Scholes - I appreciate what you say about PDF settings, but the original document was pretty weighty so I don't anticipate that the PDF size can be reduced


I think this is one for the ICAEW to raise with HMRC, if they haven't already.

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19th Jun 2012 12:42

base 64

The pdf attachments have to be base64 encoded ( ) which increases the size by a factor of 1.37

Avoid producing pdfs by scanning.

If you have no option, scan as black and white and at "fax" quality.

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