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Tax season will not allow you time to find your way. A customer brings in a W-2, 1099s, and a batch of receipts, and the small tax practitioner must have all of these documents merged into one file in the next few minutes, not after reviewing tutorials. How quickly you can perform the merger is important. However, there is another important factor that could easily slip your mind due to haste: those documents contain a person’s Social Security number and other financial information. A tool that lets you combine PDFs in seconds, without training, and without cutting corners on security, is what this specific job actually calls for. This guide compares the options.
In addition to safety and security issues, data protection obligations also exist. If a tax practice is subject to the General Data Protection Regulation (GDPR) or United Kingdom General Data Protection Regulation (UK GDPR), then the practice must examine how an online PDF tool stores, processes, transmits, and erases personal data. An online PDF tool that allows a tax preparer to merge multiple PDFs within seconds without requiring either extensive knowledge or compromising on security or privacy is exactly what this particular position requires. This article provides a comparison of the options.
Table of Contents
| Tool | Best for | Ease of use | Safety and privacy considerations | Free tier | Pricing (from) |
|---|---|---|---|---|---|
| Lumin | Fast merging with strong security for client tax data | High | SOC 2 Type 2 and AES-256 encryption; review its data processing and retention terms regarding GDPR obligations | Free plan | ~$9/month |
| Smallpdf | The fastest possible merge | Very high | Standard encryption; check deletion, hosting, and processing terms | Limited daily tasks | Free tier; paid plans |
| iLovePDF | Clear reordering for multi-document mergers | Very high | Standard encryption; review retention and international transfer arrangements | Limited daily tasks | Free tier; paid plans |
| PDFgear | Frequent merging during busy season without caps | High | Standard encryption; verify privacy, retention, and processor terms before uploading client data | Generally free | Free for core tools |
| Sejda | Occasional mergers for privacy-conscious users | High | Files deleted automatically after several hours; verify contractual and hosting details | Tight daily and file-size caps | Free tier; paid plans |
| Adobe Acrobat | Large batches of scanned client documents | Moderate | Strong security controls; business plans may provide additional administrative and contractual options | Limited free tools | Subscription |
Security specifics, privacy terms, and pricing may change over time.
Lumin permits users to take a client’s W-2, 1099s, and receipts, put them in whatever order they wish to view them in as thumbnail images via drag-and-drop ordering capabilities located in the browser window, and then merge them together into one file. Dragging and dropping the images takes seconds to master. No software download is required. You don’t have to study a user manual prior to using Lumin.
Since client tax documents include Social Security numbers and financial information, security features are equally as important as speed. Therefore, Lumin is SOC 2 Type 2 compliant and uses AES-256 encryption to protect client data both during the merge process and thereafter.
While such security features may be helpful for practices that fall under GDPR or UK GDPR obligations, they alone cannot create the necessary compliance. The practice should also evaluate the vendor’s applicable data processing agreement, file-retention terms, list of subprocessors, hosted locations of client data, deletion policies, and any agreements for cross-border transfers.
There is a legitimate free tier with Lumin. However, for the majority of practitioners who will exceed their free-tier limits, Lumin charges approximately $9 monthly. Based upon reviews from Capterra (~235 reviews) and G2 (~817 reviews), reviewers frequently comment about how easy Lumin is to use.
The purpose of Smallpdf is to be able to rapidly merge client documents via a drag-and-drop page that does not require an appreciable amount of learning. While it may serve well for occasional merging of client documents, there is less chance that you will ever need to perform frequent merging of client documents because Smallpdf has a limited ability to handle multiple client documents simultaneously.
Prior to using Smallpdf for client documents that contain personally identifiable information covered by GDPR regulations, you should review its current file-deletion, client-data-hosting, and client-data-processing policies.
When a client submits multiple documents that need to be combined into a single document in a certain sequence—for example, a W-2 first, followed by 1099s—iLovePDF displays each document as a thumbnail image, allowing the practitioner to reorder the documents prior to combining them. Allowing reordering based on thumbnails helps facilitate organizing complex mergers in advance of completing the actual merge operation.
In order to comply with GDPR regulations, practitioners should investigate how long uploaded files remain accessible online and whether personal data is transmitted internationally to countries outside the UK or EU.
As opposed to many free tiers of PDF tools that limit how many times you can perform a merge per day, PDFgear does not have such limitations during peak season, when you need to be able to continue merging files without running out of allowed merge opportunities.
Although privacy and retention terms should be reviewed prior to using PDFgear for client documents that contain personally identifiable information governed by regulatory agencies, PDFgear is likely to be a good option for rapid merging during peak season. Also, if you need to merge multiple client files quickly during peak season and are concerned about costs associated with paying for additional merge opportunities beyond your initial allotted amount of free merges, PDFgear offers an attractive alternative.
Sejda is similar to Smallpdf in that it performs merges through an internet browser and deletes files several hours after completion of the merge operation. Both services offer automatic deletion, which can help satisfy the GDPR requirement for storage limitation.
However, regardless of whether automatic deletion occurs, the practitioner must still assess the service provider’s contractual provisions relating to deletion controls, subcontractors involved with data processing, hosting locations for stored client data, and transfer mechanisms involving client data outside the UK or EU.
Adobe Acrobat is capable of efficiently handling large amounts of scanned client documents. With regard to scanning large quantities of client documents during peak season, Adobe Acrobat serves as a reliable option.
Additionally, Adobe offers various business plans that allow for the centralization of administration, implementation of role-based access control, and documentation of formal data processing agreements, which may be beneficial to tax preparation practices.
A tax preparer opening a new client’s folder needs two things simultaneously: to get the W-2, 1099s, and receipts combined into one document immediately and to ensure that the document is truly secured once completed, since it includes a Social Security number and financial information that would cause problems were it breached.
Combining the speed of Lumin with true security for sensitive tax data is unique among the options listed above. Smallpdf and iLovePDF also provide similarly quick solutions for individual merges. Adobe Acrobat is reliable for handling large stacks of scanned client documents in situations when a customer provides a large stack of receipts.
What uniquely differentiates Lumin from other solutions for this specific position is combining ease of use with true, documented security for sensitive tax data, which will be more significant than with typical document-merging tasks.
That being said, a tax practice subject to the GDPR or UK GDPR remains ultimately responsible for its own compliance. The practice typically acts as the data controller, while the PDF provider may act as a data processor.
Therefore, prior to accepting any service provider as an acceptable solution for complying with GDPR or UK GDPR regulations, the practitioner should:
During peak seasons, PDFgear will permit unlimited free merges, while Adobe will consistently provide reliability when managing large stacks of scanned client documents but will require more time to become proficient with. When you simply need to perform a one-off merge quickly, Smallpdf or iLovePDF will accomplish your task without requiring any education. Lumin will pair that same level of ease with SOC 2 and AES-256 security features designed specifically for protecting tax documents that need serious protection.
Before peak season commences, conduct a proof of concept by creating a sample client file that includes a W-2, 1099s, and a receipt or two. Measure the total amount of time spent merging your sample client file, as this is a far superior evaluation method to relying on any product listing describing features.
